# myleetcode **Repository Path**: hiyky/myleetcode ## Basic Information - **Project Name**: myleetcode - **Description**: Forked from guobinhit/myleetcode on Github. - **Primary Language**: Unknown - **License**: MIT - **Default Branch**: master - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2021-01-15 - **Last Updated**: 2021-01-15 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README # myleetcode ![author](https://img.shields.io/badge/author-chariesgavin-blueviolet.svg)![last commit](https://img.shields.io/github/last-commit/guobinhit/myleetcode.svg)![issues](https://img.shields.io/github/issues/guobinhit/myleetcode.svg)![stars](https://img.shields.io/github/stars/guobinhit/myleetcode.svg)![forks]( https://img.shields.io/github/forks/guobinhit/myleetcode.svg)![license](https://img.shields.io/github/license/guobinhit/myleetcode.svg) My LeetCode Solutions! ## Contributing Contributions are very welcome! If you see an problem that you'd like to see fixed, the best way to make it happen is to help out by submitting a pull request implementing it. Refer to the [CONTRIBUTING.md](https://github.com/guobinhit/myleetcode/blob/master/CONTRIBUTING.md) file for more details about the workflow. You can also ask for problem solving ideas and discuss in GitHub issues directly. ## INDEX - **Learn** - [Array and String](#array-and-string) - [Queue & Stack](#queue--stack) - [Linked List](#linked-list) - [Hash Table](#hash-table) - [Binary Search](#binary-search) - [Binary Tree](#binary-tree) - [Binary Search Tree](#binary-search-tree) - [N-ary Tree](#n-ary-tree) - [Trie (Prefix Tree)](#trie-prefix-tree) - [Decision Tree](#decision-tree) - [Recursion I](#recursion-i) - [Recursion II](#recursion-ii) - [Concurrency](#concurrency) - [Others](#others) - [Shell](#shell) - [Database](#database) - [Sort Algorithm](#sort-algorithm) - [Search Algorithm](#search-algorithm) - **Interview** - [Top Interview Questions](#top-interview-questions) - [Easy Collection](#easy-collection) - [Medium Collection](#medium-collection) - [Hard Collection](#hard-collection) ## Learn ### Array and String | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |14|[Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_14.java) & Python|Easy| Introduction to String |26|[Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_26.java) & Python|Easy| Conclusion |27|[Remove Element](https://leetcode.com/problems/implement-strstr/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_27.java) & Python|Easy| Two-Pointer Technique |28|[Implement strStr()](https://leetcode.com/problems/implement-strstr/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_28.java) & Python|Easy| Introduction to String |54|[Spiral Matrix](https://leetcode.com/problems/spiral-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_54.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_54.py)|Medium| Introduction to 2D Array |66|[Plus One](https://leetcode.com/problems/plus-one/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_66.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_66.py)|Easy| Introduction to Array |67|[Add Binary](https://leetcode.com/problems/add-binary/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_67.java) & Python|Easy| Introduction to String |118|[Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_118.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_118.py)| Easy| Introduction to 2D Array |119|[Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_119.java) & Python| Easy| Conclusion |151|[Reverse Words in a String](https://leetcode.com/problems/pascals-triangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_151.java) & Python| Medium| Conclusion |167|[Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_167.java) & Python| Easy| Two-Pointer Technique |189|[Rotate Array](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_189.java) & Python| Easy| Conclusion |209|[Minimum Size Subarray Sum](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_209.java) & Python| Medium| Two-Pointer Technique |283|[Move Zeroes](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_283.java) & Python| Easy| Conclusion |344|[Reverse String](https://leetcode.com/problems/reverse-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_344.java) & Python| Easy| Two-Pointer Technique |485|[Max Consecutive Ones](https://leetcode.com/problems/diagonal-traverse/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_485.java) & Python |Easy| Two-Pointer Technique |498|[Diagonal Traverse](https://leetcode.com/problems/diagonal-traverse/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_498.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_498.py) |Medium| Introduction to 2D Array |557|[Reverse Words in a String III](https://leetcode.com/problems/reverse-words-in-a-string-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_557.java) & Python |Easy| Conclusion |561|[Array Partition I](https://leetcode.com/problems/array-partition-i/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_561.java) & Python|Easy| Two-Pointer Technique |724|[Find Pivot Index](https://leetcode.com/problems/find-pivot-index/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_724.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_724.py)| Easy | Introduction to Array |747|[Largest Number Greater Than Twice of Others](https://leetcode.com/problems/largest-number-at-least-twice-of-others/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_747.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/array_and_string/_747.py)| Easy| Introduction to Array ### Queue & Stack | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |20|[Valid Parentheses](https://leetcode.com/problems/valid-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_20.java) & Python|Easy| Stack: Last-in-first-out Data Structure |133|[Clone Graph](https://leetcode.com/problems/clone-graph/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_133.java) & Python|Medium| Stack and DFS |150|[Evaluate Reverse Polish Notation](https://leetcode.com/problems/evaluate-reverse-polish-notation/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_150.java) & Python|Medium| Stack: Last-in-first-out Data Structure |155|[Min Stack](https://leetcode.com/problems/min-stack/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_155.java) & Python|Easy| Stack: Last-in-first-out Data Structure |200|[Number of Islands](https://leetcode.com/problems/number-of-islands/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_200.java) & Python|Medium| Queue and BFS |225|[Implement Stack using Queues](https://leetcode.com/problems/implement-stack-using-queues/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_225.java) & Python|Easy| Conclusion |232|[Implement Queue using Stacks](https://leetcode.com/problems/implement-queue-using-stacks/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_232.java) & Python|Easy| Conclusion |279|[Perfect Squares](https://leetcode.com/problems/perfect-squares/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_279.java) & Python|Medium| Queue and BFS |394|[Decode String](https://leetcode.com/problems/decode-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_394.java) & Python|Medium| Conclusion |494|[Target Sum](https://leetcode.com/problems/target-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_494.java) & Python|Medium| Stack and DFS |542|[01 Matrix](https://leetcode.com/problems/01-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_542.java) & Python|Medium| Conclusion |622|[Design Circular Queue](https://leetcode.com/problems/longest-common-prefix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_622.java) & Python|Medium| Queue: First-in-first-out Data Structure |733|[Flood Fill](https://leetcode.com/problems/flood-fill/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_733.java) & Python|Easy| Conclusion |739|[Daily Temperatures](https://leetcode.com/problems/daily-temperatures/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_739.java) & Python|Medium| Stack: Last-in-first-out Data Structure |752|[Open the Lock](https://leetcode.com/problems/open-the-lock/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_752.java) & Python|Medium| Queue and BFS |841|[Keys and Rooms](https://leetcode.com/problems/keys-and-rooms/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_841.java) & Python|Medium| Conclusion ### Linked List | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |2|[Add Two Numbers](https://leetcode.com/problems/add-two-numbers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_2.java) & Python|Medium| Conclusion |19|[Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_19.java) & Python|Medium| Two Pointer Technique |21|[Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_21.java) & Python|Easy| Conclusion |61|[Rotate List](https://leetcode.com/problems/rotate-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_61.java) & Python|Medium| Conclusion |135|[Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_135.java) & Python|Medium| Conclusion |141|[Linked List Cycle](https://leetcode.com/problems/number-of-islands/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_141.java) & Python|Easy| Two Pointer Technique |142|[Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_142.java) & Python|Medium| Two Pointer Technique |160|[Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_160.java) & Python|Easy| Two Pointer Technique |203|[Remove Linked List Elements](https://leetcode.com/problems/remove-linked-list-elements/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_203.java) & Python|Easy| Classic Problems |206|[Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_206.java) & Python|Easy| Classic Problems |234|[Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_234.java) & Python|Easy| Classic Problems |328|[Odd Even Linked List](https://leetcode.com/problems/odd-even-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_328.java) & Python|Medium| Classic Problems |430|[Flatten a Multilevel Doubly Linked List](https://leetcode.com/problems/flatten-a-multilevel-doubly-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_430.java) & Python|Medium| Conclusion |707|[Design Linked List](https://leetcode.com/problems/number-of-islands/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_707.java) & Python|Easy| Singly Linked List ### Hash Table | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |1|[Two Sum](https://leetcode.com/problems/two-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_1.java) & Python |Easy| Practical Application - Hash Map |3|[Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_3.java) & Python |Medium| Conclusion |36|[Valid Sudoku](https://leetcode.com/problems/valid-sudoku/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_36.java) & Python |Medium| Practical Application - Design the Key |49|[Group Anagrams](https://leetcode.com/problems/group-anagrams/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_49.java) & Python |Medium| Practical Application - Design the Key |136|[Single Number](https://leetcode.com/problems/single-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_136.java) & Python |Easy| Practical Application - Hash Set |202|[Happy Number](https://leetcode.com/problems/happy-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_202.java) & Python |Easy| Practical Application - Hash Set |205|[Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_205.java) & Python |Easy| Practical Application - Hash Map |217|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_217.java) & Python |Easy| Practical Application - Hash Set |219|[Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_219.java) & Python |Easy| Practical Application - Hash Map |347|[Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_347.java) & Python |Medium| Conclusion |349|[Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_349.java) & Python |Easy| Practical Application - Hash Set |350|[Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_350.java) & Python |Easy| Practical Application - Hash Map |380|[Insert Delete GetRandom O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_380.java) & Python |Medium| Conclusion |387|[First Unique Character in a String](https://leetcode.com/problems/first-unique-character-in-a-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_387.java) & Python |Easy| Practical Application - Hash Map |454|[4Sum II](https://leetcode.com/problems/4sum-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_454.java) & Python |Medium| Conclusion |599|[Minimum Index Sum of Two Lists](https://leetcode.com/problems/minimum-index-sum-of-two-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_599.java) & Python |Easy| Practical Application - Hash Map |652|[Find Duplicate Subtrees](https://leetcode.com/problems/find-duplicate-subtrees/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_652.java) & Python |Medium| Practical Application - Design the Key |705|[Design HashSet](https://leetcode.com/problems/design-hashset/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_705.java) & Python |Easy| Design a Hash Table |706|[Design HashMap](https://leetcode.com/problems/design-hashmap/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_706.java) & Python |Easy| Design a Hash Table |771|[Jewels and Stones](https://leetcode.com/problems/jewels-and-stones/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_771.java) & Python |Easy| Conclusion ### Binary Search | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |4|[Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_4.java) & Python |Hard| More Practices II |33|[Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_33.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_33.py)|Medium| Template I |34|[Find First and Last Position of Element in Sorted Array](https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_34.java) & Python |Medium| Template III |50|[Pow(x, n)](https://leetcode.com/problems/powx-n/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_50.java) & Python |Medium| Conclusion |69|[Sqrt(x)](https://leetcode.com/problems/sqrtx/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_69.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_69.py)|Easy| Template I |153|[Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_153.java) & Python|Medium| Template II |154|[Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_154.java) & Python| Hard| More Practices |162|[Find Peak Element](https://leetcode.com/problems/find-peak-element/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_162.java) & Python|Medium| Template II |167|[Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_167.java) & Python |Easy| More Practices |278|[First Bad Version](https://leetcode.com/problems/first-bad-version/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_278.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_278.py)|Easy| Template II |287|[Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_287.java) & Python |Medium| More Practices II |349|[Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_349.java) & Python |Easy| More Practices |350|[Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_350.java) & Python |Easy| More Practices |367|[Valid Perfect Square](https://leetcode.com/problems/valid-perfect-square/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_367.java) & Python |Easy| Conclusion |374|[Guess Number Higher or Lower](https://leetcode.com/problems/guess-number-higher-or-lower/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_374.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_374.py)|Easy| Template I |410|[Split Array Largest Sum](https://leetcode.com/problems/split-array-largest-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_410.java) & Python |Hard| More Practices II |658|[Find K Closest Elements](https://leetcode.com/problems/find-k-closest-elements/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_658.java) & Python |Medium| Template III |704|[Binary Search](https://leetcode.com/problems/binary-search/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_704.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_704.py)|Easy| Background |719|[Find K-th Smallest Pair Distance](https://leetcode.com/problems/find-k-th-smallest-pair-distance/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_719.java) & Python |Hard| More Practices II |744|[Find Smallest Letter Greater Than Target](https://leetcode.com/problems/find-smallest-letter-greater-than-target/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_744.java) & Python|Easy| Conclusion ### Binary Tree | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |94|[Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_94.java) & Python |Medium| Traverse A Tree |101|[Symmetric Tree](https://leetcode.com/problems/symmetric-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_101.java) & Python |Easy| Solve Tree Problems Recursively |102|[Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_102.java) & Python |Medium| Traverse A Tree |104|[Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_104.java) & Python |Easy| Solve Tree Problems Recursively |105|[Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_105.java) & Python |Medium| Conclusion |106|[Construct Binary Tree from Inorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_106.java) & Python |Medium| Conclusion |112|[Path Sum](https://leetcode.com/problems/path-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_112.java) & Python |Easy| Solve Tree Problems Recursively |116|[Populating Next Right Pointers in Each Node](https://leetcode.com/problems/populating-next-right-pointers-in-each-node/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_116.java) & Python |Medium| Conclusion |117|[Populating Next Right Pointers in Each Node II](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_117.java) & Python |Medium| Conclusion |144|[Binary Tree Preorder Traversal](https://leetcode.com/problems/binary-tree-preorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_144.java) & Python |Medium| Traverse A Tree |145|[Binary Tree Postorder Traversal](https://leetcode.com/problems/binary-tree-postorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_145.java) & Python |Hard| Traverse A Tree |236|[Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_236.java) & Python |Medium| Conclusion |297|[Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_297.java) & Python |Medium| Conclusion ### Binary Search Tree | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |98|[Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_98.java) & Python |Medium| Introduction to BST |108|[Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_108.java) & Python |Easy| Appendix: Height-balanced BST |110|[Balanced Binary Tree](https://leetcode.com/problems/balanced-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_110.java) & Python |Easy| Appendix: Height-balanced BST |173|[Binary Search Tree Iterator](https://leetcode.com/problems/binary-search-tree-iterator/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_173.java) & Python |Medium| Introduction to BST |220|[Contains Duplicate III](https://leetcode.com/problems/contains-duplicate-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_220.java) & Python |Medium| Conclusion |235|[Lowest Common Ancestor of a Binary Search Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_235.java) & Python |Easy| Conclusion |450|[Delete Node in a BST](https://leetcode.com/problems/delete-node-in-a-bst/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_450.java) & Python |Medium| Basic Operations in BST |700|[Search in a Binary Search Tree](https://leetcode.com/problems/search-in-a-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_700.java) & Python |Easy| Basic Operations in BST |701|[Insert into a Binary Search Tree](https://leetcode.com/problems/insert-into-a-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_701.java) & Python |Medium| Basic Operations in BST |703|[Kth Largest Element in a Stream](https://leetcode.com/problems/kth-largest-element-in-a-stream/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_703.java) & Python |Easy| Conclusion ### N-ary Tree | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |429|[N-ary Tree Level Order Traversal](https://leetcode.com/problems/n-ary-tree-level-order-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/n_ary_tree/_429.java) & Python |Easy| Traversal |559|[Maximum Depth of N-ary Tree](https://leetcode.com/problems/maximum-depth-of-n-ary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/n_ary_tree/_559.java) & Python |Easy| Recursion |589|[N-ary Tree Preorder Traversal](https://leetcode.com/problems/n-ary-tree-preorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/n_ary_tree/_589.java) & Python |Easy| Traversal |590|[N-ary Tree Postorder Traversal](https://leetcode.com/problems/n-ary-tree-postorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/n_ary_tree/_590.java) & Python |Easy| Traversal ### Trie (Prefix Tree) | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |208|[Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_208.java) & Python |Medium| Basic Operations |211|[Add and Search Word - Data structure design](https://leetcode.com/problems/add-and-search-word-data-structure-design/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_211.java) & Python |Medium| Practical Application I |212|[Word Search II](https://leetcode.com/problems/word-search-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_212.java) & Python |Hard| Practical Application II |336|[Palindrome Pairs](https://leetcode.com/problems/palindrome-pairs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_336.java) & Python |Hard| Practical Application II |421|[Maximum XOR of Two Numbers in an Array](https://leetcode.com/problems/maximum-xor-of-two-numbers-in-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_421.java) & Python |Medium| Practical Application II |648|[Replace Words](https://leetcode.com/problems/replace-words/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_648.java) & Python |Medium| Practical Application I |677|[Map Sum Pairs](https://leetcode.com/problems/map-sum-pairs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_677.java) & Python |Medium| Practical Application I ### Decision Tree | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: | ### |[Calculate Entropy](https://leetcode.com/explore/learn/card/decision-tree/285/implementation/2650/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/decision_tree/CalculateEntropy.java) & Python |Easy| Implementation | ### |[Calculate Maximum Information Gain](https://leetcode.com/explore/learn/card/decision-tree/285/implementation/2651/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/decision_tree/CalculateMaxInfoGain.java) & Python |Easy| Implementation ### Recursion I | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |21|[Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_21.java) & Python|Easy| Conclusion |24|[Swap Nodes in Pairs](https://leetcode.com/problems/swap-nodes-in-pairs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_i/_24.java) & Python| Medium| Principle of Recursion |50|[Pow(x, n)](https://leetcode.com/problems/powx-n/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_50.java) & Python |Medium| Complexity Analysis |70|[Climbing Stairs](https://leetcode.com/problems/climbing-stairs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_70.java) & Python| Easy| Memoization |95|[Unique Binary Search Trees II](https://leetcode.com/problems/unique-binary-search-trees-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_95.java) & Python|Medium| Conclusion |104|[Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_104.java) & Python |Easy| Complexity Analysis |118|[Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_118.java) & Python| Easy| Recurrence Relation |119|[Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_119.java) & Python| Easy| Recurrence Relation |206|[Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_206.java) & Python|Easy| Recurrence Relation |344|[Reverse String](https://leetcode.com/problems/reverse-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_344.java) & Python| Easy| Principle of Recursion |509|[Fibonacci Number](https://leetcode.com/problems/fibonacci-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_509.java) & Python| Easy| Memoization |779|[K-th Symbol in Grammar](https://leetcode.com/problems/k-th-symbol-in-grammar/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_779.java) & Python|Medium| Conclusion ### Recursion II | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |17|[Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_17.java) & Python |Medium| Conclusion |22|[Generate Parentheses](https://leetcode.com/problems/generate-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_22.java) & Python |Medium| Recursion to Iteration |37|[Sudoku Solver](https://leetcode.com/problems/sudoku-solver/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_37.java) & Python |Hard| Backtracking |46|[Permutations](https://leetcode.com/problems/permutations/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_46.java) & Python |Medium| Conclusion |52|[N-Queens II](https://leetcode.com/problems/n-queens-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_52.java) & Python |Hard| Backtracking |77|[Combinations](https://leetcode.com/problems/combinations/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_77.java) & Python |Medium| Backtracking |84|[Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_84.java) & Python |Hard| Conclusion |94|[Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_94.java) & Python |Medium| Recursion to Iteration |98|[Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_98.java) & Python |Medium| Divide and Conquer |100|[Same Tree](https://leetcode.com/problems/same-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_100.java) & Python |Easy| Recursion to Iteration |102|[Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_102.java) & Python |Medium| Recursion to Iteration |218|[The Skyline Problem](https://leetcode.com/problems/the-skyline-problem/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_218.java) & Python |Hard| Conclusion |240|[Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_240.java) & Python |Medium| Divide and Conquer |912|[Sort an Array](https://leetcode.com/problems/sort-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_912.java) & Python|Medium| Divide and Conquer ### Concurrency | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |1114|[Print in Order](https://leetcode.com/problems/print-in-order/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1114.java) & Python |Easy| Concurrency |1115|[Print FooBar Alternately](https://leetcode.com/problems/print-foobar-alternately/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1115.java) & Python |Medium| Concurrency |1116|[Print Zero Even Odd](https://leetcode.com/problems/print-zero-even-odd/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1116.java) & Python |Medium| Concurrency |1117|[Building H2O](https://leetcode.com/problems/building-h2o/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1117.java) & Python |Medium| Concurrency |1195|[Fizz Buzz Multithreaded](https://leetcode.com/problems/fizz-buzz-multithreaded/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1195.java) & Python |Medium| Concurrency |1226|[The Dining Philosophers](https://leetcode.com/problems/the-dining-philosophers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/concurrency/_1226.java) & Python |Medium| Concurrency ### Others | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |6|[ZigZag Conversion](https://leetcode.com/problems/zigzag-conversion/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_6.java) & Python |Medium| Others |9|[Palindrome Number](https://leetcode.com/problems/palindrome-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_9.java) & Python |Easy| Others |12|[Integer to Roman](https://leetcode.com/problems/integer-to-roman/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_12.java) & Python |Medium| Others |16|[3Sum Closest](https://leetcode.com/problems/3sum-closest/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_16.java) & Python |Medium| Others |18|[4Sum](https://leetcode.com/problems/4sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_18.java) & Python |Medium| Others |25|[Reverse Nodes in k-Group](https://leetcode.com/problems/reverse-nodes-in-k-group/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_25.java) & Python |Hard| Others |30|[Substring with Concatenation of All Words](https://leetcode.com/problems/substring-with-concatenation-of-all-words/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_30.java) & Python |Hard| Others |31|[Next Permutation](https://leetcode.com/problems/next-permutation/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_31.java) & Python |Medium| Others |32|[Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_32.java) & Python |Hard| Others |35|[Search Insert Position](https://leetcode.com/problems/search-insert-position/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_35.java) & Python |Easy| Others |39|[Combination Sum](https://leetcode.com/problems/combination-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_39.java) & Python |Medium| Others |40|[Combination Sum II](https://leetcode.com/problems/combination-sum-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_40.java) & Python |Medium| Others |43|[Multiply Strings](https://leetcode.com/problems/multiply-strings/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_43.java) & Python |Medium| Others |45|[Jump Game II](https://leetcode.com/problems/jump-game-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_45.java) & Python |Hard| Others |47|[Permutations II](https://leetcode.com/problems/permutations-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_47.java) & Python |Medium| Others |51|[N-Queens](https://leetcode.com/problems/n-queens/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_51.java) & Python |Hard| Others |57|[Insert Interval](https://leetcode.com/problems/insert-interval/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_57.java) & Python |Hard| Others |58|[Length of Last Word](https://leetcode.com/problems/length-of-last-word/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_58.java) & Python |Easy| Others |59|[Spiral Matrix II](https://leetcode.com/problems/spiral-matrix-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_59.java) & Python |Medium| Others |60|[Permutation Sequence](https://leetcode.com/problems/permutation-sequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_60.java) & Python |Medium| Others |63|[Unique Paths II](https://leetcode.com/problems/unique-paths-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_63.java) & Python |Medium| Others |64|[Minimum Path Sum](https://leetcode.com/problems/minimum-path-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_64.java) & Python |Medium| Others |65|[Valid Number](https://leetcode.com/problems/valid-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_65.java) & Python |Hard| Others |68|[Text Justification](https://leetcode.com/problems/text-justification/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_68.java) & Python |Hard| Others |71|[Simplify Path](https://leetcode.com/problems/simplify-path/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_71.java) & Python |Medium| Others |72|[Edit Distance](https://leetcode.com/problems/edit-distance/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_72.java) & Python |Hard| Others |74|[Search a 2D Matrix](https://leetcode.com/problems/search-a-2d-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_74.java) & Python |Medium| Others |80|[Remove Duplicates from Sorted Array II](https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_80.java) & Python |Medium| Others |81|[Search in Rotated Sorted Array II](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_81.java) & Python |Medium| Others |82|[Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_82.java) & Python |Medium| Others |83|[Remove Duplicates from Sorted List](https://leetcode.com/problems/remove-duplicates-from-sorted-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_83.java) & Python |Easy| Others |85|[Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_85.java) & Python |Hard| Others |86|[Partition List](https://leetcode.com/problems/partition-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_86.java) & Python |Medium| Others |87|[Scramble String](https://leetcode.com/problems/scramble-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_87.java) & Python |Hard| Others |89|[Gray Code](https://leetcode.com/problems/gray-code/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_89.java) & Python |Medium| Others |90|[Subsets II](https://leetcode.com/problems/subsets-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_90.java) & Python |Medium| Others |92|[Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_92.java) & Python |Medium| Others |93|[Restore IP Addresses](https://leetcode.com/problems/restore-ip-addresses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_93.java) & Python |Medium| Others |96|[Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_96.java) & Python |Medium| Others |97|[Interleaving String](https://leetcode.com/problems/interleaving-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_97.java) & Python |Hard| Others |99|[Recover Binary Search Tree](https://leetcode.com/problems/recover-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_99.java) & Python |Hard| Others |107|[Binary Tree Level Order Traversal II](https://leetcode.com/problems/binary-tree-level-order-traversal-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_107.java) & Python |Easy| Others |109|[Convert Sorted List to Binary Search Tree](https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_109.java) & Python |Medium| Others |111|[Minimum Depth of Binary Tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_111.java) & Python |Easy| Others |113|[Path Sum II](https://leetcode.com/problems/path-sum-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_113.java) & Python |Medium| Others |114|[Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_114.java) & Python |Medium| Others |115|[Distinct Subsequences](https://leetcode.com/problems/distinct-subsequences/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_115.java) & Python |Hard| Others |120|[Triangle](https://leetcode.com/problems/triangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_120.java) & Python |Medium| Others |123|[Best Time to Buy and Sell Stock III](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_123.java) & Python |Hard| Others |126|[Word Ladder II](https://leetcode.com/problems/word-ladder-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_126.java) & Python |Hard| Others |129|[Sum Root to Leaf Numbers](https://leetcode.com/problems/sum-root-to-leaf-numbers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_129.java) & Python |Medium| Others |132|[Palindrome Partitioning II](https://leetcode.com/problems/palindrome-partitioning-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_132.java) & Python |Hard| Others |134|[Gas Station](https://leetcode.com/problems/gas-station/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_134.java) & Python |Medium| Others |135|[Candy](https://leetcode.com/problems/candy/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_135.java) & Python |Hard| Others |137|[Single Number II](https://leetcode.com/problems/single-number-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_137.java) & Python |Medium| Others |143|[Reorder List](https://leetcode.com/problems/reorder-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_143.java) & Python |Medium| Others |147|[Insertion Sort List](https://leetcode.com/problems/insertion-sort-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_147.java) & Python |Medium| Others |164|[Maximum Gap](https://leetcode.com/problems/maximum-gap/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_164.java) & Python |Hard| Others |165|[Compare Version Numbers](https://leetcode.com/problems/compare-version-numbers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_165.java) & Python |Medium| Others |168|[Excel Sheet Column Title](https://leetcode.com/problems/excel-sheet-column-title/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_168.java) & Python |Easy| Others |174|[Dungeon Game](https://leetcode.com/problems/dungeon-game/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_174.java) & Python |Hard| Others |187|[Repeated DNA Sequences](https://leetcode.com/problems/repeated-dna-sequences/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_187.java) & Python |Medium| Others |188|[Best Time to Buy and Sell Stock IV](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_188.java) & Python |Hard| Others |199|[Binary Tree Right Side View](https://leetcode.com/problems/binary-tree-right-side-view/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_199.java) & Python |Medium| Others |201|[Bitwise AND of Numbers Range](https://leetcode.com/problems/bitwise-and-of-numbers-range/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_201.java) & Python |Medium| Others |213|[House Robber II](https://leetcode.com/problems/house-robber-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_213.java) & Python |Medium| Others |214|[Shortest Palindrome](https://leetcode.com/problems/shortest-palindrome/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_214.java) & Python |Hard| Others |216|[Combination Sum III](https://leetcode.com/problems/combination-sum-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_216.java) & Python |Medium| Others |221|[Maximal Square](https://leetcode.com/problems/maximal-square/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_221.java) & Python |Medium| Others |222|[Count Complete Tree Nodes](https://leetcode.com/problems/count-complete-tree-nodes/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_222.java) & Python |Medium| Others |223|[Rectangle Area](https://leetcode.com/problems/rectangle-area/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_223.java) & Python |Medium| Others |224|[Basic Calculator](https://leetcode.com/problems/basic-calculator/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_224.java) & Python |Hard| Others |226|[Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_226.java) & Python |Easy| Others |228|[Summary Ranges](https://leetcode.com/problems/summary-ranges/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_228.java) & Python |Medium| Others |229|[Majority Element II](https://leetcode.com/problems/majority-element-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_229.java) & Python |Medium| Others |231|[Power of Two](https://leetcode.com/problems/power-of-two/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_231.java) & Python |Easy| Others |233|[Number of Digit One](https://leetcode.com/problems/number-of-digit-one/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_233.java) & Python |Hard| Others |241|[Different Ways to Add Parentheses](https://leetcode.com/problems/different-ways-to-add-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_241.java) & Python |Medium| Others |257|[Binary Tree Paths](https://leetcode.com/problems/binary-tree-paths/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_257.java) & Python |Easy| Others |258|[Add Digits](https://leetcode.com/problems/add-digits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_258.java) & Python |Easy| Others |260|[Single Number III](https://leetcode.com/problems/single-number-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_260.java) & Python |Medium| Others |263|[Ugly Number](https://leetcode.com/problems/ugly-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_263.java) & Python |Easy| Others |264|[Ugly Number II](https://leetcode.com/problems/ugly-number-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_264.java) & Python |Medium| Others |273|[Integer to English Words](https://leetcode.com/problems/integer-to-english-words/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_273.java) & Python |Hard| Others |274|[H-Index](https://leetcode.com/problems/h-index/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_274.java) & Python |Medium| Others |275|[H-Index II](https://leetcode.com/problems/h-index-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_275.java) & Python |Medium| Others |282|[Expression Add Operators](https://leetcode.com/problems/expression-add-operators/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_282.java) & Python |Hard| Others |284|[Peeking Iterator](https://leetcode.com/problems/peeking-iterator/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_284.java) & Python |Medium| Others |290|[Word Pattern](https://leetcode.com/problems/word-pattern/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_290.java) & Python |Easy| Others |292|[Nim Game](https://leetcode.com/problems/nim-game/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_292.java) & Python |Easy| Others |299|[Bulls and Cows](https://leetcode.com/problems/bulls-and-cows/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_299.java) & Python |Easy| Others |303|[Range Sum Query - Immutable](https://leetcode.com/problems/range-sum-query-immutable/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_303.java) & Python |Easy| Others |304|[Range Sum Query 2D - Immutable](https://leetcode.com/problems/range-sum-query-2d-immutable/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_304.java) & Python |Medium| Others |306|[Additive Number](https://leetcode.com/problems/additive-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_306.java) & Python |Medium| Others |307|[Range Sum Query - Mutable](https://leetcode.com/problems/range-sum-query-mutable/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_307.java) & Python |Medium| Others |310|[Minimum Height Trees](https://leetcode.com/problems/minimum-height-trees/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_310.java) & Python |Medium| Others |313|[Super Ugly Number](https://leetcode.com/problems/super-ugly-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_313.java) & Python |Medium| Others |316|[Remove Duplicate Letters](https://leetcode.com/problems/remove-duplicate-letters/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_316.java) & Python |Hard| Others |318|[Maximum Product of Word Lengths](https://leetcode.com/problems/maximum-product-of-word-lengths/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_318.java) & Python |Medium| Others |319|[Bulb Switcher](https://leetcode.com/problems/bulb-switcher/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_319.java) & Python |Medium| Others |321|[Create Maximum Number](https://leetcode.com/problems/create-maximum-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_321.java) & Python |Hard| Others |327|[Count of Range Sum](https://leetcode.com/problems/count-of-range-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_327.java) & Python |Hard| Others |330|[Patching Array](https://leetcode.com/problems/patching-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_330.java) & Python |Hard| Others |331|[Verify Preorder Serialization of a Binary Tree](https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_331.java) & Python |Medium| Others |332|[Reconstruct Itinerary](https://leetcode.com/problems/reconstruct-itinerary/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_332.java) & Python |Medium| Others |335|[Self Crossing](https://leetcode.com/problems/self-crossing/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_335.java) & Python |Hard| Others |337|[House Robber III](https://leetcode.com/problems/house-robber-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_337.java) & Python |Medium| Others |338|[Counting Bits](https://leetcode.com/problems/counting-bits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_338.java) & Python |Medium| Others |342|[Power of Four](https://leetcode.com/problems/power-of-four/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_342.java) & Python |Easy| Others |343|[Integer Break](https://leetcode.com/problems/integer-break/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_343.java) & Python |Medium| Others |345|[Reverse Vowels of a String](https://leetcode.com/problems/reverse-vowels-of-a-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_345.java) & Python |Easy| Others |352|[Data Stream as Disjoint Intervals](https://leetcode.com/problems/data-stream-as-disjoint-intervals/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_352.java) & Python |Hard| Others |354|[Russian Doll Envelopes](https://leetcode.com/problems/russian-doll-envelopes/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_354.java) & Python |Hard| Others |355|[Design Twitter](https://leetcode.com/problems/design-twitter/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_355.java) & Python |Medium| Others |357|[Count Numbers with Unique Digits](https://leetcode.com/problems/count-numbers-with-unique-digits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_357.java) & Python |Medium| Others |363|[Max Sum of Rectangle No Larger Than K](https://leetcode.com/problems/max-sum-of-rectangle-no-larger-than-k/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_363.java) & Python |Hard| Others |365|[Water and Jug Problem](https://leetcode.com/problems/water-and-jug-problem/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_365.java) & Python |Medium| Others |368|[Largest Divisible Subset](https://leetcode.com/problems/largest-divisible-subset/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_368.java) & Python |Medium| Others |372|[Super Pow](https://leetcode.com/problems/super-pow/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_372.java) & Python |Medium| Others |373|[Find K Pairs with Smallest Sums](https://leetcode.com/problems/find-k-pairs-with-smallest-sums/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_373.java) & Python |Medium| Others |375|[Guess Number Higher or Lower II](https://leetcode.com/problems/guess-number-higher-or-lower-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_375.java) & Python |Medium| Others |376|[Wiggle Subsequence](https://leetcode.com/problems/wiggle-subsequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_376.java) & Python |Medium| Others |377|[Combination Sum IV](https://leetcode.com/problems/combination-sum-iv/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_377.java) & Python |Medium| Others |381|[Insert Delete GetRandom O(1) - Duplicates allowed](https://leetcode.com/problems/insert-delete-getrandom-o1-duplicates-allowed/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_381.java) & Python |Hard| Others |382|[Linked List Random Node](https://leetcode.com/problems/linked-list-random-node/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_382.java) & Python |Medium| Others |383|[Ransom Note](https://leetcode.com/problems/ransom-note/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_383.java) & Python |Easy| Others |385|[Mini Parser](https://leetcode.com/problems/mini-parser/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_385.java) & Python |Medium| Others |386|[Lexicographical Numbers](https://leetcode.com/problems/lexicographical-numbers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_386.java) & Python |Medium| Others |388|[Longest Absolute File Path](https://leetcode.com/problems/longest-absolute-file-path/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_388.java) & Python |Medium| Others |389|[Find the Difference](https://leetcode.com/problems/find-the-difference/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_389.java) & Python |Easy| Others |390|[Elimination Game](https://leetcode.com/problems/elimination-game/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_390.java) & Python |Medium| Others |391|[Perfect Rectangle](https://leetcode.com/problems/perfect-rectangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_391.java) & Python |Hard| Others |392|[Is Subsequence](https://leetcode.com/problems/is-subsequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_392.java) & Python |Easy| Others |393|[UTF-8 Validation](https://leetcode.com/problems/utf-8-validation/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_393.java) & Python |Medium| Others |395|[Longest Substring with At Least K Repeating Characters](https://leetcode.com/problems/longest-substring-with-at-least-k-repeating-characters/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_395.java) & Python |Medium| Others |396|[Rotate Function](https://leetcode.com/problems/rotate-function/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_396.java) & Python |Medium| Others |397|[Integer Replacement](https://leetcode.com/problems/integer-replacement/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_397.java) & Python |Medium| Others |398|[Random Pick Index](https://leetcode.com/problems/random-pick-index/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_398.java) & Python |Medium| Others |399|[Evaluate Division](https://leetcode.com/problems/evaluate-division/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_399.java) & Python |Medium| Others |400|[Nth Digit](https://leetcode.com/problems/nth-digit/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_400.java) & Python |Medium| Others |401|[Binary Watch](https://leetcode.com/problems/binary-watch/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_401.java) & Python |Easy| Others |402|[Remove K Digits](https://leetcode.com/problems/remove-k-digits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_402.java) & Python |Medium| Others |403|[Frog Jump](https://leetcode.com/problems/frog-jump/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_403.java) & Python |Hard| Others |404|[Sum of Left Leaves](https://leetcode.com/problems/sum-of-left-leaves/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_404.java) & Python |Easy| Others |405|[Convert a Number to Hexadecimal](https://leetcode.com/problems/convert-a-number-to-hexadecimal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_405.java) & Python |Easy| Others |407|[Trapping Rain Water II](https://leetcode.com/problems/trapping-rain-water-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_407.java) & Python |Hard| Others |409|[Longest Palindrome](https://leetcode.com/problems/longest-palindrome/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_409.java) & Python |Easy| Others |413|[Arithmetic Slices](https://leetcode.com/problems/arithmetic-slices/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_413.java) & Python |Medium| Others |414|[Third Maximum Number](https://leetcode.com/problems/third-maximum-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_414.java) & Python |Easy| Others |415|[Add Strings](https://leetcode.com/problems/add-strings/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_415.java) & Python |Easy| Others |416|[Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_416.java) & Python |Medium| Others |417|[Pacific Atlantic Water Flow](https://leetcode.com/problems/pacific-atlantic-water-flow/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_417.java) & Python |Medium| Others |419|[Battleships in a Board](https://leetcode.com/problems/battleships-in-a-board/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_419.java) & Python |Medium| Others |420|[Strong Password Checker](https://leetcode.com/problems/strong-password-checker/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_420.java) & Python |Hard| Others |423|[Reconstruct Original Digits from English](https://leetcode.com/problems/reconstruct-original-digits-from-english/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_423.java) & Python |Medium| Others |424|[Longest Repeating Character Replacement](https://leetcode.com/problems/longest-repeating-character-replacement/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_424.java) & Python |Medium| Others |427|[Construct Quad Tree](https://leetcode.com/problems/construct-quad-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_427.java) & Python |Medium| Others |432|[All O\`one Data Structure](https://leetcode.com/problems/all-oone-data-structure/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_432.java) & Python |Hard| Others |433|[Minimum Genetic Mutation](https://leetcode.com/problems/minimum-genetic-mutation/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_433.java) & Python |Medium| Others |434|[Number of Segments in a String](https://leetcode.com/problems/number-of-segments-in-a-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_434.java) & Python |Easy| Others |435|[Non-overlapping Intervals](https://leetcode.com/problems/non-overlapping-intervals/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_435.java) & Python |Medium| Others |436|[Find Right Interval](https://leetcode.com/problems/find-right-interval/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_436.java) & Python |Medium| Others |437|[Path Sum III](https://leetcode.com/problems/path-sum-iii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_437.java) & Python |Easy| Others |438|[Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_438.java) & Python |Medium| Others |440|[K-th Smallest in Lexicographical Order](https://leetcode.com/problems/k-th-smallest-in-lexicographical-order/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_440.java) & Python |Hard| Others |441|[Arranging Coins](https://leetcode.com/problems/arranging-coins/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_441.java) & Python |Easy| Others |442|[Find All Duplicates in an Array](https://leetcode.com/problems/find-all-duplicates-in-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_442.java) & Python |Medium| Others |443|[String Compression](https://leetcode.com/problems/string-compression/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_443.java) & Python |Easy| Others |445|[Add Two Numbers II](https://leetcode.com/problems/add-two-numbers-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_445.java) & Python |Medium| Others |446|[Arithmetic Slices II - Subsequence](https://leetcode.com/problems/arithmetic-slices-ii-subsequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_446.java) & Python |Hard| Others |447|[Number of Boomerangs](https://leetcode.com/problems/number-of-boomerangs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_447.java) & Python |Easy| Others |448|[Find All Numbers Disappeared in an Array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_448.java) & Python |Easy| Others |449|[Serialize and Deserialize BST](https://leetcode.com/problems/serialize-and-deserialize-bst/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_449.java) & Python |Medium| Others |451|[Sort Characters By Frequency](https://leetcode.com/problems/sort-characters-by-frequency/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_451.java) & Python |Medium| Others |452|[Minimum Number of Arrows to Burst Balloons](https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_452.java) & Python |Medium| Others |453|[Minimum Moves to Equal Array Elements](https://leetcode.com/problems/minimum-moves-to-equal-array-elements/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_453.java) & Python |Easy| Others |455|[Assign Cookies](https://leetcode.com/problems/assign-cookies/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_455.java) & Python |Easy| Others |456|[132 Pattern](https://leetcode.com/problems/132-pattern/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_456.java) & Python |Medium| Others |457|[Circular Array Loop](https://leetcode.com/problems/circular-array-loop/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_457.java) & Python |Medium| Others |458|[Poor Pigs](https://leetcode.com/problems/poor-pigs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_458.java) & Python |Hard| Others |459|[Repeated Substring Pattern](https://leetcode.com/problems/repeated-substring-pattern/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_459.java) & Python |Easy| Others |460|[LFU Cache](https://leetcode.com/problems/lfu-cache/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_460.java) & Python |Hard| Others |462|[Minimum Moves to Equal Array Elements II](https://leetcode.com/problems/minimum-moves-to-equal-array-elements-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_462.java) & Python |Medium| Others |463|[Island Perimeter](https://leetcode.com/problems/island-perimeter/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_463.java) & Python |Easy| Others |464|[Can I Win](https://leetcode.com/problems/can-i-win/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_464.java) & Python |Medium| Others |466|[Count The Repetitions](https://leetcode.com/problems/count-the-repetitions/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_466.java) & Python |Hard| Others |467|[Unique Substrings in Wraparound String](https://leetcode.com/problems/unique-substrings-in-wraparound-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_467.java) & Python |Medium| Others |468|[Validate IP Address](https://leetcode.com/problems/validate-ip-address/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_468.java) & Python |Medium| Others |470|[Implement Rand10() Using Rand7()](https://leetcode.com/problems/implement-rand10-using-rand7/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_470.java) & Python |Medium| Others |472|[Concatenated Words](https://leetcode.com/problems/concatenated-words/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_472.java) & Python |Hard| Others |473|[Matchsticks to Square](https://leetcode.com/problems/matchsticks-to-square/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_473.java) & Python |Medium| Others |474|[Ones and Zeroes](https://leetcode.com/problems/ones-and-zeroes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_474.java) & Python |Medium| Others |475|[Heaters](https://leetcode.com/problems/heaters/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_475.java) & Python |Easy| Others |476|[Number Complement](https://leetcode.com/problems/number-complement/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_476.java) & Python |Easy| Others |477|[Total Hamming Distance](https://leetcode.com/problems/total-hamming-distance/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_477.java) & Python |Medium| Others |478|[Generate Random Point in a Circle](https://leetcode.com/problems/generate-random-point-in-a-circle/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_478.java) & Python |Medium| Others |479|[Largest Palindrome Product](https://leetcode.com/problems/largest-palindrome-product/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_479.java) & Python |Hard| Others |480|[Sliding Window Median](https://leetcode.com/problems/sliding-window-median/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_480.java) & Python |Hard| Others |481|[Magical String](https://leetcode.com/problems/magical-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_481.java) & Python |Medium| Others |482|[License Key Formatting](https://leetcode.com/problems/license-key-formatting/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_482.java) & Python |Easy| Others |483|[Smallest Good Base](https://leetcode.com/problems/smallest-good-base/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_483.java) & Python |Hard| Others |486|[Predict the Winner](https://leetcode.com/problems/predict-the-winner/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_486.java) & Python |Medium| Others |488|[Zuma Game](https://leetcode.com/problems/zuma-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_488.java) & Python |Hard| Others |491|[Increasing Subsequences](https://leetcode.com/problems/increasing-subsequences/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_491.java) & Python |Medium| Others |492|[Construct the Rectangle](https://leetcode.com/problems/construct-the-rectangle/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_492.java) & Python |Easy| Others |493|[Reverse Pairs](https://leetcode.com/problems/reverse-pairs/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_493.java) & Python |Hard| Others |495|[Teemo Attacking](https://leetcode.com/problems/teemo-attacking/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_495.java) & Python |Medium| Others |496|[Next Greater Element I](https://leetcode.com/problems/next-greater-element-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_496.java) & Python |Easy| Others |497|[Random Point in Non-overlapping Rectangles](https://leetcode.com/problems/random-point-in-non-overlapping-rectangles/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_497.java) & Python |Medium| Others |500|[Keyboard Row](https://leetcode.com/problems/keyboard-row/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_500.java) & Python |Easy| Others |501|[Find Mode in Binary Search Tree](https://leetcode.com/problems/find-mode-in-binary-search-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_501.java) & Python |Easy| Others |502|[IPO](https://leetcode.com/problems/ipo/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_502.java) & Python |Hard| Others |503|[Next Greater Element II](https://leetcode.com/problems/next-greater-element-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_503.java) & Python |Medium| Others |504|[Base 7](https://leetcode.com/problems/base-7/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_504.java) & Python |Easy| Others |506|[Relative Ranks](https://leetcode.com/problems/relative-ranks/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_506.java) & Python |Easy| Others |507|[Perfect Number](https://leetcode.com/problems/perfect-number/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_507.java) & Python |Easy| Others |508|[Most Frequent Subtree Sum](https://leetcode.com/problems/most-frequent-subtree-sum/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_508.java) & Python |Medium| Others |513|[Find Bottom Left Tree Value](https://leetcode.com/problems/find-bottom-left-tree-value/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_513.java) & Python |Medium| Others |514|[Freedom Trail](https://leetcode.com/problems/freedom-trail/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_514.java) & Python |Hard| Others |515|[Find Largest Value in Each Tree Row](https://leetcode.com/problems/find-largest-value-in-each-tree-row/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_515.java) & Python |Medium| Others |516|[Longest Palindromic Subsequence](https://leetcode.com/problems/longest-palindromic-subsequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_516.java) & Python |Medium| Others |517|[Super Washing Machines](https://leetcode.com/problems/super-washing-machines/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_517.java) & Python |Hard| Others |518|[Coin Change 2](https://leetcode.com/problems/coin-change-2/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_518.java) & Python |Medium| Others |519|[Random Flip Matrix](https://leetcode.com/problems/random-flip-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_519.java) & Python |Medium| Others |520|[Detect Capital](https://leetcode.com/problems/detect-capital/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_520.java) & Python |Easy| Others |521|[Longest Uncommon Subsequence I](https://leetcode.com/problems/longest-uncommon-subsequence-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_521.java) & Python |Easy| Others |522|[Longest Uncommon Subsequence II](https://leetcode.com/problems/longest-uncommon-subsequence-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_522.java) & Python |Medium| Others |523|[Continuous Subarray Sum](https://leetcode.com/problems/continuous-subarray-sum/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_523.java) & Python |Medium| Others |524|[Longest Word in Dictionary through Deleting](https://leetcode.com/problems/longest-word-in-dictionary-through-deleting/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_524.java) & Python |Medium| Others |525|[Contiguous Array](https://leetcode.com/problems/contiguous-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_525.java) & Python |Medium| Others |526|[Beautiful Arrangement](https://leetcode.com/problems/beautiful-arrangement/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_526.java) & Python |Medium| Others |528|[Random Pick with Weight](https://leetcode.com/problems/random-pick-with-weight/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_528.java) & Python |Medium| Others |529|[Minesweeper](https://leetcode.com/problems/minesweeper/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_529.java) & Python |Medium| Others |530|[Minimum Absolute Difference in BST](https://leetcode.com/problems/minimum-absolute-difference-in-bst/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_530.java) & Python |Easy| Others |532|[K-diff Pairs in an Array](https://leetcode.com/problems/k-diff-pairs-in-an-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_532.java) & Python |Easy| Others |535|[Encode and Decode TinyURL](https://leetcode.com/problems/encode-and-decode-tinyurl/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_535.java) & Python |Medium| Others |537|[Complex Number Multiplication](https://leetcode.com/problems/complex-number-multiplication/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_537.java) & Python |Medium| Others |538|[Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_538.java) & Python |Easy| Others |539|[Minimum Time Difference](https://leetcode.com/problems/minimum-time-difference/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_539.java) & Python |Medium| Others |540|[Single Element in a Sorted Array](https://leetcode.com/problems/single-element-in-a-sorted-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_540.java) & Python |Medium| Others |541|[Reverse String II](https://leetcode.com/problems/reverse-string-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_541.java) & Python |Easy| Others |543|[Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_543.java) & Python |Easy| Others |546|[Remove Boxes](https://leetcode.com/problems/remove-boxes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_546.java) & Python |Hard| Others |551|[Student Attendance Record I](https://leetcode.com/problems/student-attendance-record-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_551.java) & Python |Easy| Others |552|[Student Attendance Record II](https://leetcode.com/problems/student-attendance-record-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_552.java) & Python |Hard| Others |553|[Optimal Division](https://leetcode.com/problems/optimal-division/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_553.java) & Python |Medium| Others |554|[Brick Wall](https://leetcode.com/problems/brick-wall/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_554.java) & Python |Medium| Others |556|[Next Greater Element III](https://leetcode.com/problems/next-greater-element-iii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_556.java) & Python |Medium| Others |558|[Quad Tree Intersection](https://leetcode.com/problems/quad-tree-intersection/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_558.java) & Python |Easy| Others |560|[Subarray Sum Equals K](https://leetcode.com/problems/subarray-sum-equals-k/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_560.java) & Python |Medium| Others |563|[Binary Tree Tilt](https://leetcode.com/problems/binary-tree-tilt/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_563.java) & Python |Easy| Others |564|[Find the Closest Palindrome](https://leetcode.com/problems/find-the-closest-palindrome/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_564.java) & Python |Hard| Others |565|[Array Nesting](https://leetcode.com/problems/array-nesting/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_565.java) & Python |Medium| Others |566|[Reshape the Matrix](https://leetcode.com/problems/reshape-the-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_566.java) & Python |Easy| Others |567|[Permutation in String](https://leetcode.com/problems/permutation-in-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_567.java) & Python |Medium| Others |572|[Subtree of Another Tree](https://leetcode.com/problems/subtree-of-another-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_572.java) & Python |Easy| Others |575|[Distribute Candies](https://leetcode.com/problems/distribute-candies/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_575.java) & Python |Easy| Others |576|[Out of Boundary Paths](https://leetcode.com/problems/out-of-boundary-paths/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_576.java) & Python |Medium| Others |581|[Shortest Unsorted Continuous Subarray](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_581.java) & Python |Easy| Others |583|[Delete Operation for Two Strings](https://leetcode.com/problems/delete-operation-for-two-strings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_583.java) & Python |Medium| Others |587|[Erect the Fence](https://leetcode.com/problems/erect-the-fence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_587.java) & Python |Hard| Others |591|[Tag Validator](https://leetcode.com/problems/tag-validator/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_591.java) & Python |Hard| Others |592|[Fraction Addition and Subtraction](https://leetcode.com/problems/fraction-addition-and-subtraction/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_592.java) & Python |Medium| Others |593|[Valid Square](https://leetcode.com/problems/valid-square/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_593.java) & Python |Medium| Others |594|[Longest Harmonious Subsequence](https://leetcode.com/problems/longest-harmonious-subsequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_594.java) & Python |Easy| Others |598|[Range Addition II](https://leetcode.com/problems/range-addition-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_598.java) & Python |Easy| Others |600|[Non-negative Integers without Consecutive Ones](https://leetcode.com/problems/non-negative-integers-without-consecutive-ones/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_600.java) & Python |Hard| Others |605|[Can Place Flowers](https://leetcode.com/problems/can-place-flowers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_605.java) & Python |Easy| Others |606|[Construct String from Binary Tree](https://leetcode.com/problems/construct-string-from-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_606.java) & Python |Easy| Others |609|[Find Duplicate File in System](https://leetcode.com/problems/find-duplicate-file-in-system/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_609.java) & Python |Medium| Others |611|[Valid Triangle Number](https://leetcode.com/problems/valid-triangle-number/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_611.java) & Python |Medium| Others |617|[Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_617.java) & Python |Easy| Others |623|[Add One Row to Tree](https://leetcode.com/problems/add-one-row-to-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_623.java) & Python |Medium| Others |628|[Maximum Product of Three Numbers](https://leetcode.com/problems/maximum-product-of-three-numbers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_628.java) & Python |Easy| Others |629|[K Inverse Pairs Array](https://leetcode.com/problems/k-inverse-pairs-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_629.java) & Python |Hard| Others |630|[Course Schedule III](https://leetcode.com/problems/course-schedule-iii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_630.java) & Python |Hard| Others |632|[Smallest Range Covering Elements from K Lists](https://leetcode.com/problems/smallest-range-covering-elements-from-k-lists/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_632.java) & Python |Hard| Others |633|[Sum of Square Numbers](https://leetcode.com/problems/sum-of-square-numbers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_633.java) & Python |Easy| Others |636|[Exclusive Time of Functions](https://leetcode.com/problems/exclusive-time-of-functions/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_636.java) & Python |Medium| Others |637|[Average of Levels in Binary Tree](https://leetcode.com/problems/average-of-levels-in-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_637.java) & Python |Easy| Others |638|[Shopping Offers](https://leetcode.com/problems/shopping-offers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_638.java) & Python |Medium| Others |639|[Decode Ways II](https://leetcode.com/problems/decode-ways-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_639.java) & Python |Hard| Others |640|[Solve the Equation](https://leetcode.com/problems/solve-the-equation/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_640.java) & Python |Medium| Others |641|[Design Circular Deque](https://leetcode.com/problems/design-circular-deque/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_641.java) & Python |Medium| Others |643|[Maximum Average Subarray I](https://leetcode.com/problems/maximum-average-subarray-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_643.java) & Python |Easy| Others |645|[Set Mismatch](https://leetcode.com/problems/set-mismatch/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_645.java) & Python |Easy| Others |646|[Maximum Length of Pair Chain](https://leetcode.com/problems/maximum-length-of-pair-chain/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_646.java) & Python |Medium| Others |647|[Palindromic Substrings](https://leetcode.com/problems/palindromic-substrings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_647.java) & Python |Medium| Others |649|[Dota2 Senate](https://leetcode.com/problems/dota2-senate/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_649.java) & Python |Medium| Others |650|[2 Keys Keyboard](https://leetcode.com/problems/2-keys-keyboard/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_650.java) & Python |Medium| Others |653|[Two Sum IV - Input is a BST](https://leetcode.com/problems/two-sum-iv-input-is-a-bst/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_653.java) & Python |Easy| Others |654|[Maximum Binary Tree](https://leetcode.com/problems/maximum-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_654.java) & Python |Medium| Others |655|[Print Binary Tree](https://leetcode.com/problems/print-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_655.java) & Python |Medium| Others |657|[Robot Return to Origin](https://leetcode.com/problems/robot-return-to-origin/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_657.java) & Python |Easy| Others |659|[Split Array into Consecutive Subsequences](https://leetcode.com/problems/split-array-into-consecutive-subsequences/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_659.java) & Python |Medium| Others |661|[Image Smoother](https://leetcode.com/problems/image-smoother/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_661.java) & Python |Easy| Others |662|[Maximum Width of Binary Tree](https://leetcode.com/problems/maximum-width-of-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_662.java) & Python |Medium| Others |664|[Strange Printer](https://leetcode.com/problems/strange-printer/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_664.java) & Python |Hard| Others |665|[Non-decreasing Array](https://leetcode.com/problems/non-decreasing-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_665.java) & Python |Easy| Others |667|[Beautiful Arrangement II](https://leetcode.com/problems/beautiful-arrangement-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_667.java) & Python |Medium| Others |668|[Kth Smallest Number in Multiplication Table](https://leetcode.com/problems/kth-smallest-number-in-multiplication-table/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_668.java) & Python |Hard| Others |669|[Trim a Binary Search Tree](https://leetcode.com/problems/trim-a-binary-search-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_669.java) & Python |Easy| Others |670|[Maximum Swap](https://leetcode.com/problems/maximum-swap/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_670.java) & Python |Medium| Others |671|[Second Minimum Node In a Binary Tree](https://leetcode.com/problems/second-minimum-node-in-a-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_671.java) & Python |Easy| Others |672|[Bulb Switcher II](https://leetcode.com/problems/bulb-switcher-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_672.java) & Python |Medium| Others |673|[Number of Longest Increasing Subsequence](https://leetcode.com/problems/number-of-longest-increasing-subsequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_673.java) & Python |Medium| Others |674|[Longest Continuous Increasing Subsequence](https://leetcode.com/problems/longest-continuous-increasing-subsequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_674.java) & Python |Easy| Others |675|[Cut Off Trees for Golf Event](https://leetcode.com/problems/cut-off-trees-for-golf-event/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_675.java) & Python |Hard| Others |676|[Implement Magic Dictionary](https://leetcode.com/problems/implement-magic-dictionary/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_676.java) & Python |Medium| Others |678|[Valid Parenthesis String](https://leetcode.com/problems/valid-parenthesis-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_678.java) & Python |Medium| Others |679|[24 Game](https://leetcode.com/problems/24-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_679.java) & Python |Hard| Others |680|[Valid Palindrome II](https://leetcode.com/problems/valid-palindrome-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_680.java) & Python |Easy| Others |682|[Baseball Game](https://leetcode.com/problems/baseball-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_682.java) & Python |Easy| Others |684|[Redundant Connection](https://leetcode.com/problems/redundant-connection/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_684.java) & Python |Medium| Others |685|[Redundant Connection II](https://leetcode.com/problems/redundant-connection-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_685.java) & Python |Hard| Others |686|[Repeated String Match](https://leetcode.com/problems/repeated-string-match/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_686.java) & Python |Easy| Others |687|[Longest Univalue Path](https://leetcode.com/problems/longest-univalue-path/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_687.java) & Python |Easy| Others |688|[Knight Probability in Chessboard](https://leetcode.com/problems/knight-probability-in-chessboard/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_688.java) & Python |Medium| Others |689|[Maximum Sum of 3 Non-Overlapping Subarrays](https://leetcode.com/problems/maximum-sum-of-3-non-overlapping-subarrays/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_689.java) & Python |Hard| Others |690|[Employee Importance](https://leetcode.com/problems/employee-importance/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_690.java) & Python |Easy| Others |691|[Stickers to Spell Word](https://leetcode.com/problems/stickers-to-spell-word/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_691.java) & Python |Hard| Others |692|[Top K Frequent Words](https://leetcode.com/problems/top-k-frequent-words/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_692.java) & Python |Medium| Others |693|[Binary Number with Alternating Bits](https://leetcode.com/problems/binary-number-with-alternating-bits/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_693.java) & Python |Easy| Others |695|[Max Area of Island](https://leetcode.com/problems/max-area-of-island/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_695.java) & Python |Medium| Others |696|[Count Binary Substrings](https://leetcode.com/problems/count-binary-substrings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_696.java) & Python |Easy| Others |697|[Degree of an Array](https://leetcode.com/problems/degree-of-an-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_697.java) & Python |Easy| Others |698|[Partition to K Equal Sum Subsets](https://leetcode.com/problems/partition-to-k-equal-sum-subsets/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_698.java) & Python |Medium| Others |699|[Falling Squares](https://leetcode.com/problems/falling-squares/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_699.java) & Python |Hard| Others |709|[To Lower Case](https://leetcode.com/problems/to-lower-case/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_709.java) & Python |Easy| Others |710|[Random Pick with Blacklist](https://leetcode.com/problems/random-pick-with-blacklist/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_710.java) & Python |Hard| Others |712|[Minimum ASCII Delete Sum for Two Strings](https://leetcode.com/problems/minimum-ascii-delete-sum-for-two-strings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_712.java) & Python |Medium| Others |713|[Subarray Product Less Than K](https://leetcode.com/problems/subarray-product-less-than-k/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_713.java) & Python |Medium| Others |714|[Best Time to Buy and Sell Stock with Transaction Fee](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_714.java) & Python |Medium| Others |715|[Range Module](https://leetcode.com/problems/range-module/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_715.java) & Python |Hard| Others |717|[1-bit and 2-bit Characters](https://leetcode.com/problems/1-bit-and-2-bit-characters/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_717.java) & Python |Easy| Others |718|[Maximum Length of Repeated Subarray](https://leetcode.com/problems/maximum-length-of-repeated-subarray/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_718.java) & Python |Medium| Others |720|[Longest Word in Dictionary](https://leetcode.com/problems/longest-word-in-dictionary/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_720.java) & Python |Easy| Others |721|[Accounts Merge](https://leetcode.com/problems/accounts-merge/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_721.java) & Python |Medium| Others |722|[Remove Comments](https://leetcode.com/problems/remove-comments/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_722.java) & Python |Medium| Others |725|[Split Linked List in Parts](https://leetcode.com/problems/split-linked-list-in-parts/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_725.java) & Python |Medium| Others |726|[Number of Atoms](https://leetcode.com/problems/number-of-atoms/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_726.java) & Python |Hard| Others |728|[Self Dividing Numbers](https://leetcode.com/problems/self-dividing-numbers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_728.java) & Python |Easy| Others |729|[My Calendar I](https://leetcode.com/problems/my-calendar-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_729.java) & Python |Medium| Others |730|[Count Different Palindromic Subsequences](https://leetcode.com/problems/count-different-palindromic-subsequences/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_730.java) & Python |Hard| Others |731|[My Calendar II](https://leetcode.com/problems/my-calendar-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_731.java) & Python |Medium| Others |732|[My Calendar III](https://leetcode.com/problems/my-calendar-iii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_732.java) & Python |Hard| Others |735|[Asteroid Collision](https://leetcode.com/problems/asteroid-collision/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_735.java) & Python |Medium| Others |736|[Parse Lisp Expression](https://leetcode.com/problems/parse-lisp-expression/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_736.java) & Python |Hard| Others |738|[Monotone Increasing Digits](https://leetcode.com/problems/monotone-increasing-digits/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_738.java) & Python |Medium| Others |740|[Delete and Earn](https://leetcode.com/problems/delete-and-earn/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_740.java) & Python |Medium| Others |741|[Cherry Pickup](https://leetcode.com/problems/cherry-pickup/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_741.java) & Python |Hard| Others |743|[Network Delay Time](https://leetcode.com/problems/network-delay-time/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_743.java) & Python |Medium| Others |745|[Prefix and Suffix Search](https://leetcode.com/problems/prefix-and-suffix-search/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_745.java) & Python |Hard| Others |746|[Min Cost Climbing Stairs](https://leetcode.com/problems/min-cost-climbing-stairs/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_746.java) & Python |Easy| Others |748|[Shortest Completing Word](https://leetcode.com/problems/shortest-completing-word/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_748.java) & Python |Easy| Others |749|[Contain Virus](https://leetcode.com/problems/contain-virus/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_749.java) & Python |Hard| Others |753|[Cracking the Safe](https://leetcode.com/problems/cracking-the-safe/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_753.java) & Python |Hard| Others |754|[Reach a Number](https://leetcode.com/problems/reach-a-number/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_754.java) & Python |Easy| Others |756|[Pyramid Transition Matrix](https://leetcode.com/problems/pyramid-transition-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_756.java) & Python |Medium| Others |757|[Set Intersection Size At Least Two](https://leetcode.com/problems/set-intersection-size-at-least-two/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_757.java) & Python |Hard| Others |761|[Special Binary String](https://leetcode.com/problems/special-binary-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_761.java) & Python |Hard| Others |762|[Prime Number of Set Bits in Binary Representation](https://leetcode.com/problems/prime-number-of-set-bits-in-binary-representation/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_762.java) & Python |Easy| Others |763|[Partition Labels](https://leetcode.com/problems/partition-labels/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_763.java) & Python |Medium| Others |764|[Largest Plus Sign](https://leetcode.com/problems/largest-plus-sign/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_764.java) & Python |Medium| Others |765|[Couples Holding Hands](https://leetcode.com/problems/couples-holding-hands/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_765.java) & Python |Hard| Others |766|[Toeplitz Matrix](https://leetcode.com/problems/toeplitz-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_766.java) & Python |Easy| Others |767|[Reorganize String](https://leetcode.com/problems/reorganize-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_767.java) & Python |Medium| Others |768|[Max Chunks To Make Sorted II](https://leetcode.com/problems/max-chunks-to-make-sorted-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_768.java) & Python |Hard| Others |769|[Max Chunks To Make Sorted](https://leetcode.com/problems/max-chunks-to-make-sorted/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_769.java) & Python |Medium| Others |770|[Basic Calculator IV](https://leetcode.com/problems/basic-calculator-iv/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_770.java) & Python |Hard| Others |773|[Sliding Puzzle](https://leetcode.com/problems/sliding-puzzle/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_773.java) & Python |Hard| Others |775|[Global and Local Inversions](https://leetcode.com/problems/global-and-local-inversions/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_775.java) & Python |Medium| Others |777|[Swap Adjacent in LR String](https://leetcode.com/problems/swap-adjacent-in-lr-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_777.java) & Python |Medium| Others |778|[Swim in Rising Water](https://leetcode.com/problems/swim-in-rising-water/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_778.java) & Python |Hard| Others |780|[Reaching Points](https://leetcode.com/problems/reaching-points/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_780.java) & Python |Hard| Others |781|[Rabbits in Forest](https://leetcode.com/problems/rabbits-in-forest/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_781.java) & Python |Medium| Others |782|[Transform to Chessboard](https://leetcode.com/problems/transform-to-chessboard/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_782.java) & Python |Hard| Others |783|[Minimum Distance Between BST Nodes](https://leetcode.com/problems/minimum-distance-between-bst-nodes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_783.java) & Python |Easy| Others |784|[Letter Case Permutation](https://leetcode.com/problems/letter-case-permutation/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_784.java) & Python |Easy| Others |785|[Is Graph Bipartite?](https://leetcode.com/problems/is-graph-bipartite/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_785.java) & Python |Medium| Others |786|[K-th Smallest Prime Fraction](https://leetcode.com/problems/k-th-smallest-prime-fraction/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_786.java) & Python |Hard| Others |787|[Cheapest Flights Within K Stops](https://leetcode.com/problems/cheapest-flights-within-k-stops/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_787.java) & Python |Medium| Others |788|[Rotated Digits](https://leetcode.com/problems/rotated-digits/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_788.java) & Python |Easy| Others |789|[Escape The Ghosts](https://leetcode.com/problems/escape-the-ghosts/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_789.java) & Python |Medium| Others |790|[Domino and Tromino Tiling](https://leetcode.com/problems/domino-and-tromino-tiling/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_790.java) & Python |Medium| Others |791|[Custom Sort String](https://leetcode.com/problems/custom-sort-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_791.java) & Python |Medium| Others |792|[Number of Matching Subsequences](https://leetcode.com/problems/number-of-matching-subsequences/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_792.java) & Python |Medium| Others |793|[Preimage Size of Factorial Zeroes Function](https://leetcode.com/problems/preimage-size-of-factorial-zeroes-function/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_793.java) & Python |Hard| Others |794|[Valid Tic-Tac-Toe State](https://leetcode.com/problems/valid-tic-tac-toe-state/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_794.java) & Python |Medium| Others |795|[Number of Subarrays with Bounded Maximum](https://leetcode.com/problems/number-of-subarrays-with-bounded-maximum/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_795.java) & Python |Medium| Others |796|[Rotate String](https://leetcode.com/problems/rotate-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_796.java) & Python |Easy| Others |797|[All Paths From Source to Target](https://leetcode.com/problems/all-paths-from-source-to-target/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_797.java) & Python |Medium| Others |798|[Smallest Rotation with Highest Score](https://leetcode.com/problems/smallest-rotation-with-highest-score/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_798.java) & Python |Hard| Others |799|[Champagne Tower](https://leetcode.com/problems/champagne-tower/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_799.java) & Python |Medium| Others |801|[Minimum Swaps To Make Sequences Increasing](https://leetcode.com/problems/minimum-swaps-to-make-sequences-increasing/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_801.java) & Python |Medium| Others |802|[Find Eventual Safe States](https://leetcode.com/problems/find-eventual-safe-states/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_802.java) & Python |Medium| Others |803|[Bricks Falling When Hit](https://leetcode.com/problems/bricks-falling-when-hit/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_803.java) & Python |Hard| Others |804|[Unique Morse Code Words](https://leetcode.com/problems/unique-morse-code-words/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_804.java) & Python |Easy| Others |805|[Split Array With Same Average](https://leetcode.com/problems/split-array-with-same-average/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_805.java) & Python |Hard| Others |806|[Number of Lines To Write String](https://leetcode.com/problems/number-of-lines-to-write-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_806.java) & Python |Easy| Others |807|[Max Increase to Keep City Skyline](https://leetcode.com/problems/max-increase-to-keep-city-skyline/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_807.java) & Python |Medium| Others |808|[Soup Servings](https://leetcode.com/problems/soup-servings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_808.java) & Python |Medium| Others |809|[Expressive Words](https://leetcode.com/problems/expressive-words/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_809.java) & Python |Medium| Others |810|[Chalkboard XOR Game](https://leetcode.com/problems/chalkboard-xor-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_810.java) & Python |Hard| Others |811|[Subdomain Visit Count](https://leetcode.com/problems/subdomain-visit-count/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_811.java) & Python |Easy| Others |812|[Largest Triangle Area](https://leetcode.com/problems/largest-triangle-area/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_.java) & Python |Easy| Others |813|[Largest Sum of Averages](https://leetcode.com/problems/largest-sum-of-averages/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_813.java) & Python |Medium| Others |814|[Binary Tree Pruning](https://leetcode.com/problems/binary-tree-pruning/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_814.java) & Python |Medium| Others |815|[Bus Routes](https://leetcode.com/problems/bus-routes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_815.java) & Python |Hard| Others |816|[Ambiguous Coordinates](https://leetcode.com/problems/ambiguous-coordinates/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_816.java) & Python |Medium| Others |817|[Linked List Components](https://leetcode.com/problems/linked-list-components/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_817.java) & Python |Medium| Others |818|[Race Car ](https://leetcode.com/problems/most-common-word/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_818.java) & Python |Hard| Others |819|[Most Common Word](https://leetcode.com/problems/most-common-word/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_819.java) & Python |Easy| Others |820|[Short Encoding of Words](https://leetcode.com/problems/short-encoding-of-words/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_820.java) & Python |Medium| Others |821|[Shortest Distance to a Character](https://leetcode.com/problems/shortest-distance-to-a-character/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_821.java) & Python |Easy| Others |822|[Card Flipping Game](https://leetcode.com/problems/card-flipping-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_822.java) & Python |Medium| Others |823|[Binary Trees With Factors](https://leetcode.com/problems/binary-trees-with-factors/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_823.java) & Python |Medium| Others |824|[Goat Latin](https://leetcode.com/problems/goat-latin/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_824.java) & Python |Easy| Others |825|[Friends Of Appropriate Ages](https://leetcode.com/problems/friends-of-appropriate-ages/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_825.java) & Python |Medium| Others |826|[Most Profit Assigning Work](https://leetcode.com/problems/most-profit-assigning-work/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_826.java) & Python |Medium| Others |827|[Making A Large Island](https://leetcode.com/problems/making-a-large-island/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_827.java) & Python |Hard| Others |828|[Unique Letter String](https://leetcode.com/problems/unique-letter-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_828.java) & Python |Hard| Others |829|[Consecutive Numbers Sum](https://leetcode.com/problems/consecutive-numbers-sum/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_829.java) & Python |Hard| Others |830|[Positions of Large Groups](https://leetcode.com/problems/positions-of-large-groups/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_830.java) & Python |Easy| Others |831|[Masking Personal Information](https://leetcode.com/problems/masking-personal-information/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_831.java) & Python |Medium| Others |832|[Flipping an Image](https://leetcode.com/problems/flipping-an-image/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_832.java) & Python |Easy| Others |833|[Find And Replace in String](https://leetcode.com/problems/find-and-replace-in-string/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_833.java) & Python |Medium| Others |834|[Sum of Distances in Tree](https://leetcode.com/problems/sum-of-distances-in-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_834.java) & Python |Hard| Others |835|[Image Overlap](https://leetcode.com/problems/image-overlap/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_835.java) & Python |Medium| Others |836|[Rectangle Overlap](https://leetcode.com/problems/rectangle-overlap/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_836.java) & Python |Easy| Others |837|[New 21 Game](https://leetcode.com/problems/new-21-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_837.java) & Python |Medium| Others |838|[Push Dominoes](https://leetcode.com/problems/push-dominoes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_838.java) & Python |Medium| Others |839|[Similar String Groups](https://leetcode.com/problems/similar-string-groups/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_839.java) & Python |Hard| Others |840|[Magic Squares In Grid](https://leetcode.com/problems/magic-squares-in-grid/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_840.java) & Python |Easy| Others |842|[Split Array into Fibonacci Sequence](https://leetcode.com/problems/split-array-into-fibonacci-sequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_842.java) & Python |Medium| Others |843|[Guess the Word](https://leetcode.com/problems/guess-the-word/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_843.java) & Python |Hard| Others |844|[Backspace String Compare](https://leetcode.com/problems/backspace-string-compare/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_844.java) & Python |Easy| Others |845|[Longest Mountain in Array](https://leetcode.com/problems/longest-mountain-in-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_845.java) & Python |Medium| Others |846|[Hand of Straights](https://leetcode.com/problems/hand-of-straights/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_846.java) & Python |Medium| Others |847|[Shortest Path Visiting All Nodes](https://leetcode.com/problems/shortest-path-visiting-all-nodes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_847.java) & Python |Hard| Others |848|[Shifting Letters](https://leetcode.com/problems/shifting-letters/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_848.java) & Python |Medium| Others |849|[Maximize Distance to Closest Person](https://leetcode.com/problems/maximize-distance-to-closest-person/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_849.java) & Python |Easy| Others |850|[Rectangle Area II](https://leetcode.com/problems/rectangle-area-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_850.java) & Python |Hard| Others |851|[Loud and Rich](https://leetcode.com/problems/loud-and-rich/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_851.java) & Python |Medium| Others |852|[Peak Index in a Mountain Array](https://leetcode.com/problems/peak-index-in-a-mountain-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_852.java) & Python |Easy| Others |853|[Car Fleet](https://leetcode.com/problems/car-fleet/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_853.java) & Python |Medium| Others |854|[K-Similar Strings](https://leetcode.com/problems/k-similar-strings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_854.java) & Python |Hard| Others |855|[Exam Room](https://leetcode.com/problems/exam-room/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_855.java) & Python |Medium| Others |856|[Score of Parentheses](https://leetcode.com/problems/score-of-parentheses/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_856.java) & Python |Medium| Others |857|[Minimum Cost to Hire K Workers](https://leetcode.com/problems/minimum-cost-to-hire-k-workers/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_857.java) & Python |Hard| Others |858|[Mirror Reflection](https://leetcode.com/problems/mirror-reflection/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_858.java) & Python |Medium| Others |859|[Buddy Strings](https://leetcode.com/problems/buddy-strings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_859.java) & Python |Easy| Others |860|[Lemonade Change](https://leetcode.com/problems/lemonade-change/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_860.java) & Python |Easy| Others |861|[Score After Flipping Matrix](https://leetcode.com/problems/score-after-flipping-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_861.java) & Python |Medium| Others |862|[Shortest Subarray with Sum at Least K](https://leetcode.com/problems/shortest-subarray-with-sum-at-least-k/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_862.java) & Python |Hard| Others |863|[All Nodes Distance K in Binary Tree](https://leetcode.com/problems/all-nodes-distance-k-in-binary-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_863.java) & Python |Medium| Others |864|[Shortest Path to Get All Keys](https://leetcode.com/problems/shortest-path-to-get-all-keys/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_864.java) & Python |Hard| Others |865|[Smallest Subtree with all the Deepest Nodes](https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_865.java) & Python |Medium| Others |866|[Prime Palindrome](https://leetcode.com/problems/prime-palindrome/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_866.java) & Python |Medium| Others |867|[Transpose Matrix](https://leetcode.com/problems/transpose-matrix/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_867.java) & Python |Easy| Others |868|[Binary Gap](https://leetcode.com/problems/binary-gap/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_868.java) & Python |Easy| Others |869|[Reordered Power of 2](https://leetcode.com/problems/reordered-power-of-2/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_869.java) & Python |Medium| Others |870|[Advantage Shuffle](https://leetcode.com/problems/advantage-shuffle/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_870.java) & Python |Medium| Others |871|[Minimum Number of Refueling Stops](https://leetcode.com/problems/minimum-number-of-refueling-stops/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_871.java) & Python |Hard| Others |872|[Leaf-Similar Trees](https://leetcode.com/problems/leaf-similar-trees/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_872.java) & Python |Easy| Others |873|[Length of Longest Fibonacci Subsequence](https://leetcode.com/problems/length-of-longest-fibonacci-subsequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_873.java) & Python |Medium| Others |874|[Walking Robot Simulation](https://leetcode.com/problems/walking-robot-simulation/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_874.java) & Python |Easy| Others |875|[Koko Eating Bananas](https://leetcode.com/problems/koko-eating-bananas/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_875.java) & Python |Medium| Others |876|[Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_876.java) & Python |Easy| Others |877|[Stone Game](https://leetcode.com/problems/stone-game/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_877.java) & Python |Medium| Others |878|[Nth Magical Number](https://leetcode.com/problems/nth-magical-number/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_878.java) & Python |Hard| Others |879|[Profitable Schemes](https://leetcode.com/problems/profitable-schemes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_879.java) & Python |Hard| Others |880|[Decoded String at Index](https://leetcode.com/problems/decoded-string-at-index/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_880.java) & Python |Medium| Others |881|[Boats to Save People](https://leetcode.com/problems/boats-to-save-people/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_881.java) & Python |Medium| Others |882|[Reachable Nodes In Subdivided Graph](https://leetcode.com/problems/reachable-nodes-in-subdivided-graph/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_882.java) & Python |Hard| Others |883|[Projection Area of 3D Shapes](https://leetcode.com/problems/projection-area-of-3d-shapes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_883.java) & Python |Easy| Others |884|[Uncommon Words from Two Sentences](https://leetcode.com/problems/uncommon-words-from-two-sentences/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_884.java) & Python |Easy| Others |885|[Spiral Matrix III](https://leetcode.com/problems/spiral-matrix-iii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_885.java) & Python |Medium| Others |886|[Possible Bipartition](https://leetcode.com/problems/possible-bipartition/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_886.java) & Python |Medium| Others |887|[Super Egg Drop](https://leetcode.com/problems/super-egg-drop/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_887.java) & Python |Hard| Others |888|[Fair Candy Swap](https://leetcode.com/problems/fair-candy-swap/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_888.java) & Python |Easy| Others |889|[Construct Binary Tree from Preorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-postorder-traversal/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_889.java) & Python |Medium| Others |890|[Find and Replace Pattern](https://leetcode.com/problems/find-and-replace-pattern/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_890.java) & Python |Medium| Others |891|[Sum of Subsequence Widths](https://leetcode.com/problems/sum-of-subsequence-widths/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_891.java) & Python |Hard| Others |892|[Surface Area of 3D Shapes](https://leetcode.com/problems/surface-area-of-3d-shapes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_892.java) & Python |Easy| Others |893|[Groups of Special-Equivalent Strings](https://leetcode.com/problems/groups-of-special-equivalent-strings/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_893.java) & Python |Easy| Others |894|[All Possible Full Binary Trees](https://leetcode.com/problems/all-possible-full-binary-trees/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_894.java) & Python |Medium| Others |895|[Maximum Frequency Stack](https://leetcode.com/problems/maximum-frequency-stack/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_895.java) & Python |Hard| Others |896|[Monotonic Array](https://leetcode.com/problems/monotonic-array/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_896.java) & Python |Easy| Others |897|[Increasing Order Search Tree](https://leetcode.com/problems/increasing-order-search-tree/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_897.java) & Python |Easy| Others |898|[Bitwise ORs of Subarrays](https://leetcode.com/problems/bitwise-ors-of-subarrays/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_898.java) & Python |Medium| Others |899|[Orderly Queue](https://leetcode.com/problems/orderly-queue/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_899.java) & Python |Hard| Others |900|[RLE Iterator](https://leetcode.com/problems/rle-iterator/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_900.java) & Python |Medium| Others |901|[Online Stock Span](https://leetcode.com/problems/online-stock-span/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_901.java) & Python |Medium| Others |902|[Numbers At Most N Given Digit Set](https://leetcode.com/problems/numbers-at-most-n-given-digit-set/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_902.java) & Python |Hard| Others |903|[Valid Permutations for DI Sequence](https://leetcode.com/problems/valid-permutations-for-di-sequence/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_903.java) & Python |Hard| Others |904|[Fruit Into Baskets](https://leetcode.com/problems/fruit-into-baskets/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_904.java) & Python |Medium| Others |905|[Sort Array By Parity](https://leetcode.com/problems/sort-array-by-parity/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_905.java) & Python |Easy| Others |906|[Super Palindromes](https://leetcode.com/problems/super-palindromes/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_906.java) & Python |Hard| Others |907|[Sum of Subarray Minimums](https://leetcode.com/problems/sum-of-subarray-minimums/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_907.java) & Python |Medium| Others |908|[Smallest Range I](https://leetcode.com/problems/smallest-range-i/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_908.java) & Python |Easy| Others |909|[Snakes and Ladders](https://leetcode.com/problems/snakes-and-ladders/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_909.java) & Python |Medium| Others |910|[Smallest Range II](https://leetcode.com/problems/smallest-range-ii/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_910.java) & Python |Medium| Others |911|[Online Election](https://leetcode.com/problems/online-election/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_911.java) & Python |Medium| Others |913|[Cat and Mouse](https://leetcode.com/problems/cat-and-mouse/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_913.java) & Python |Hard| Others |914|[X of a Kind in a Deck of Cards](https://leetcode.com/problems/x-of-a-kind-in-a-deck-of-cards/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_914.java) & Python |Easy| Others |915|[Partition Array into Disjoint Intervals ](https://leetcode.com/problems/partition-array-into-disjoint-intervals/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/others/_915.java) & Python |Medium| Others ### Shell | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |192|[Word Frequency](https://leetcode.com/problems/word-frequency/description/)|[bash](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/shell/_192.sh) |Medium| Shell |193|[Valid Phone Numbers](https://leetcode.com/problems/valid-phone-numbers/description/)|[bash](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/shell/_193.sh) |Easy| Shell |194|[Transpose File](https://leetcode.com/problems/transpose-file/description/)|[bash](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/shell/_194.sh) |Medium| Shell |195|[Tenth Line](https://leetcode.com/problems/tenth-line/description/)|[bash](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/shell/_195.sh) |Easy| Shell ### Database | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |175|[Combine Two Tables](https://leetcode.com/problems/combine-two-tables/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_175.sql) |Easy| Database |176|[Second Highest Salary](https://leetcode.com/problems/second-highest-salary/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_176.sql) |Easy| Database |177|[Nth Highest Salary](https://leetcode.com/problems/nth-highest-salary/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_177.sql) |Medium| Database |178|[Rank Scores](https://leetcode.com/problems/rank-scores/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_178.sql) |Medium| Database |180|[Consecutive Numbers](https://leetcode.com/problems/consecutive-numbers/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_180.sql) |Medium| Database |181|[Employees Earning More Than Their Managers](https://leetcode.com/problems/employees-earning-more-than-their-managers/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_181.sql) |Easy| Database |182|[Duplicate Emails](https://leetcode.com/problems/duplicate-emails/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_182.sql) |Easy| Database |183|[Customers Who Never Order](https://leetcode.com/problems/customers-who-never-order/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_183.sql) |Easy| Database |184|[Department Highest Salary](https://leetcode.com/problems/department-highest-salary/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_184.sql) |Medium| Database |185|[Department Top Three Salaries](https://leetcode.com/problems/department-top-three-salaries/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_185.sql) |Hard| Database |196|[Delete Duplicate Emails](https://leetcode.com/problems/delete-duplicate-emails/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_196.sql) |Easy| Database |197|[Rising Temperature](https://leetcode.com/problems/rising-temperature/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_197.sql) |Easy| Database |262|[Trips and Users](https://leetcode.com/problems/trips-and-users/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_262.sql) |Hard| Database |595|[Big Countries](https://leetcode.com/problems/big-countries/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_595.sql) |Easy| Database |596|[Classes More Than 5 Students](https://leetcode.com/problems/classes-more-than-5-students/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_596.sql) |Easy| Database |601|[Human Traffic of Stadium](https://leetcode.com/problems/human-traffic-of-stadium/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_601.sql) |Hard| Database |620|[Not Boring Movies](https://leetcode.com/problems/not-boring-movies/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_620.sql) |Easy| Database |626|[Exchange Seats](https://leetcode.com/problems/exchange-seats/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_626.sql) |Medium| Database |627|[Swap Salary](https://leetcode.com/problems/swap-salary/description/)|[MySQL](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/database/_627.sql) |Easy| Database ### Sort Algorithm | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |Sort 1|[Bubble Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/BubbleSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/BubbleSort.py)|Easy| Sort Algorithm |Sort 2|[Insert Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/InsertSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/InsertSort.py)|Easy| Sort Algorithm |Sort 3|[Select Sort](https://github.com/guobinhit/myleetcode#sort-algorithm) | [Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/SelectSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/SelectSort.py)|Easy| Sort Algorithm |Sort 4|[Quick Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/QuickSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/QuickSort.py)|Easy| Sort Algorithm |Sort 5|[Merge Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/MergeSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/MergeSort.py)|Medium| Sort Algorithm |Sort 6|[Heap Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/HeapSort.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/sort_algorithm/HeapSort.py)|Medium| Sort Algorithm |Sort 7|[Bucket Sort](https://github.com/guobinhit/myleetcode#sort-algorithm)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/sort_algorithm/BucketSort.java) & Python|Easy| Sort Algorithm ### Search Algorithm | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |Search 1|[Binary Search](https://github.com/guobinhit/myleetcode#search-algorithm) | [Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/search_algorithm/BinarySearch.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/search_algorithm/BinarySearch.py)|Easy| Search Algorithm |Search 2|[Interpolation Search](https://github.com/guobinhit/myleetcode#search-algorithm) | [Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/search_algorithm/InterpolationSearch.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/search_algorithm/InterpolationSearch.py)|Easy| Search Algorithmx |Search 3|[Order Search](https://github.com/guobinhit/myleetcode#search-algorithm) | [Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basinfo/search_algorithm/OrderSearch.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basinfo/search_algorithm/OrderSearch.py)|Easy| Search Algorithm ## Interview ### Top Interview Questions #### Easy Collection | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |1|[Two Sum](https://leetcode.com/problems/two-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_1.java) & Python |Easy| Array |7|[Reverse Integer](https://leetcode.com/problems/reverse-integer/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/strings/_7.java) & Python |Easy| Strings |8|[String to Integer (atoi)](https://leetcode.com/problems/string-to-integer-atoi/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/strings/_8.java) & Python |Medium| Strings |13|[Roman to Integer](https://leetcode.com/problems/roman-to-integer/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/math/_13.java) & Python |Easy| Math |14|[Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_14.java) & Python|Easy| Strings |19|[Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_19.java) & Python|Medium| Linked List |20|[Valid Parentheses](https://leetcode.com/problems/valid-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_20.java) & Python|Easy| Others |21|[Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_21.java) & Python|Easy| Linked List |26|[Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_26.java) & Python|Easy| Array |28|[Implement strStr()](https://leetcode.com/problems/implement-strstr/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_28.java) & Python|Easy| Strings |36|[Valid Sudoku](https://leetcode.com/problems/valid-sudoku/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_36.java) & Python |Medium| Array |38|[Count and Say](https://leetcode.com/problems/count-and-say/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/strings/_38.java) & Python |Easy| Strings |48|[Rotate Image](https://leetcode.com/problems/rotate-image/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/array/_48.java) & Python |Medium| Array |53|[Maximum Subarray](https://leetcode.com/problems/maximum-subarray/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/dynamic_programming/_53.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/interview/top_interview_questions/easy_collection/dynamic_programming/_53.py) |Easy| Dynamic Programming |66|[Plus One](https://leetcode.com/problems/plus-one/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_66.java) & Python|Easy| Array |70|[Climbing Stairs](https://leetcode.com/problems/climbing-stairs/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_70.java) & Python| Easy| Dynamic Programming |88|[Merge Sorted Array](https://leetcode.com/problems/merge-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/sorting_and_searching/_88.java) & Python |Easy| Sorting and Searching |98|[Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_98.java) & Python |Medium| Trees |101|[Symmetric Tree](https://leetcode.com/problems/symmetric-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_101.java) & Python |Easy| Trees |102|[Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_102.java) & Python |Medium| Trees |104|[Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_104.java) & Python |Easy| Trees |108|[Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_108.java) & Python |Easy| Trees |118|[Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_118.java) & Python| Easy| Others |121|[Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/dynamic_programming/_121.java) & Python |Easy| Dynamic Programming |122|[Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/array/_122.java) & Python|Easy| Array |125|[Valid Palindrome](https://leetcode.com/problems/valid-palindrome/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/strings/_125.java) & Python |Easy| Strings |136|[Single Number](https://leetcode.com/problems/single-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_136.java) & Python |Easy| Array |141|[Linked List Cycle](https://leetcode.com/problems/number-of-islands/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_141.java) & Python|Easy| Linked List |155|[Min Stack](https://leetcode.com/problems/min-stack/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_155.java) & Python|Easy| Design |189|[Rotate Array](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_189.java) & Python| Easy| Array |190|[Reverse Bits](https://leetcode.com/problems/reverse-bits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/others/_190.java) & Python |Easy| Others |191|[Number of 1 Bits](https://leetcode.com/problems/number-of-1-bits/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/others/_191.java) & Python |Easy| Others |198|[House Robber](https://leetcode.com/problems/house-robber/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/dynamic_programming/_198.java) & Python |Easy| Dynamic Programming |204|[Count Primes](https://leetcode.com/problems/count-primes/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/math/_204.java) & Python |Easy| Math |206|[Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_206.java) & Python|Easy| Linked List |217|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_217.java) & Python |Easy| Array |234|[Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_234.java) & Python|Easy| Linked List |237|[Delete Node in a Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/linked_list/_237.java) & Python |Easy| Linked List |242|[Valid Anagram](https://leetcode.com/problems/valid-anagram/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/strings/_242.java) & Python |Easy| Strings |268|[Missing Number](https://leetcode.com/problems/missing-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/others/_268.java) & Python |Easy| Others |278|[First Bad Version](https://leetcode.com/problems/first-bad-version/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_278.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_278.py)|Easy| Sorting and Searching |283|[Move Zeroes](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_283.java) & Python| Easy| Array |326|[Power of Three](https://leetcode.com/problems/power-of-three/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/math/_326.java) & Python |Easy| Math |344|[Reverse String](https://leetcode.com/problems/reverse-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_344.java) & Python| Easy| Strings |350|[Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_350.java) & Python |Easy| Array |384|[Shuffle an Array](https://leetcode.com/problems/shuffle-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/design/_384.java) & Python |Medium| Design |387|[First Unique Character in a String](https://leetcode.com/problems/first-unique-character-in-a-string/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_387.java) & Python |Easy| Strings |412|[Fizz Buzz](https://leetcode.com/problems/fizz-buzz/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/math/_412.java) & Python |Easy| Math |461|[Hamming Distance](https://leetcode.com/problems/hamming-distance/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/easy_collection/others/_461.java) & Python |Easy| Others #### Medium Collection | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |2|[Add Two Numbers](https://leetcode.com/problems/add-two-numbers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_2.java) & Python|Medium| Linked List |3|[Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_3.java) & Python |Medium| Array and Strings |5|[Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_5.java) & Python |Medium| Array and Strings |15|[3Sum](https://leetcode.com/problems/3sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_15.java) & Python |Medium| Array and Strings |17|[Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/recursion_ii/_17.java) & Python |Medium| Backtracking |22|[Generate Parentheses](https://leetcode.com/problems/generate-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_22.java) & Python |Medium| Backtracking |29|[Divide Two Integers](https://leetcode.com/problems/divide-two-integers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/math/_29.java) & Python |Medium| Math |33|[Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_33.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_33.py)|Medium| Sorting and Searching |34|[Find First and Last Position of Element in Sorted Array](https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_34.java) & Python |Medium| Sorting and Searching |46|[Permutations](https://leetcode.com/problems/permutations/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_46.java) & Python |Medium| Backtracking |49|[Group Anagrams](https://leetcode.com/problems/group-anagrams/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_49.java) & Python |Medium| Array and Strings |50|[Pow(x, n)](https://leetcode.com/problems/powx-n/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_50.java) & Python |Medium| Math |55|[Jump Game](https://leetcode.com/problems/jump-game/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/dynamic_programming/_55.java) & Python |Medium| Dynamic Programming |56|[Merge Intervals](https://leetcode.com/problems/merge-intervals/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/sorting_and_searching/_56.java) & Python |Medium| Sorting and Searching |62|[Unique Paths](https://leetcode.com/problems/unique-paths/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/dynamic_programming/_62.java) & Python |Medium| Dynamic Programming |69|[Sqrt(x)](https://leetcode.com/problems/sqrtx/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_69.java) & [Python](https://github.com/guobinhit/myleetcode/blob/master/codes/python/leetcodes/src/main/python/com/hit/basmath/learn/binary_search/_69.py)|Easy| Math |73|[Set Matrix Zeroes](https://leetcode.com/problems/set-matrix-zeroes/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_73.java) & Python |Medium| Array and Strings |75|[Sort Colors](https://leetcode.com/problems/sort-colors/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/sorting_and_searching/_75.java) & Python |Medium| Sorting and Searching |78|[Subsets](https://leetcode.com/problems/subsets/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_78.java) & Python |Medium| Backtracking |79|[Word Search](https://leetcode.com/problems/word-search/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_79.java) & Python |Medium| Backtracking |94|[Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_94.java) & Python |Medium| Trees and Graphs |103|[Binary Tree Zigzag Level Order Traversal](https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/trees_and_graphs/_103.java) & Python |Medium| Trees and Graphs |105|[Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_105.java) & Python |Medium| Trees and Graphs |116|[Populating Next Right Pointers in Each Node](https://leetcode.com/problems/populating-next-right-pointers-in-each-node/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_116.java) & Python |Medium| Trees and Graphs |150|[Evaluate Reverse Polish Notation](https://leetcode.com/problems/evaluate-reverse-polish-notation/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_150.java) & Python|Medium| Others |160|[Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_160.java) & Python|Easy| Linked List |162|[Find Peak Element](https://leetcode.com/problems/find-peak-element/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_162.java) & Python|Medium| Sorting and Searching |166|[Fraction to Recurring Decimal](https://leetcode.com/problems/fraction-to-recurring-decimal/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/math/_166.java) & Python |Medium| Math |169|[Majority Element](https://leetcode.com/problems/majority-element/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/others/_169.java) & Python |Easy| Others |171|[Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/math/_171.java) & Python |Easy| Math |172|[Factorial Trailing Zeroes](https://leetcode.com/problems/factorial-trailing-zeroes/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/math/_172.java) & Python |Easy| Math |200|[Number of Islands](https://leetcode.com/problems/number-of-islands/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_200.java) & Python|Medium| Trees and Graphs |202|[Happy Number](https://leetcode.com/problems/happy-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_202.java) & Python |Easy| Math |215|[Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/sorting_and_searching/_215.java) & Python |Medium| Sorting and Searching |230|[Kth Smallest Element in a BST](https://leetcode.com/problems/kth-smallest-element-in-a-bst/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/trees_and_graphs/_230.java) & Python |Medium| Trees and Graphs |240|[Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_240.java) & Python |Medium| Sorting and Searching |297|[Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_297.java) & Python |Medium| Design |300|[Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/dynamic_programming/_300.java) & Python |Medium| Dynamic Programming |322|[Coin Change](https://leetcode.com/problems/coin-change/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/dynamic_programming/_322.java) & Python |Medium| Dynamic Programming |328|[Odd Even Linked List](https://leetcode.com/problems/odd-even-linked-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_328.java) & Python|Medium| Linked List |334|[Increasing Triplet Subsequence](https://leetcode.com/problems/increasing-triplet-subsequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/array_and_strings/_334.java) & Python |Medium| Array and Strings |347|[Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_347.java) & Python |Medium| Sorting and Searching |371|[Sum of Two Integers](https://leetcode.com/problems/sum-of-two-integers/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/others/_371.java) & Python |Easy| Others |380|[Insert Delete GetRandom O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_380.java) & Python |Medium| Design |621|[Task Scheduler](https://leetcode.com/problems/task-scheduler/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/medium_collection/others/_621.java) & Python |Medium| Others #### Hard Collection | # | Title | Solutions | Difficulty | Tag |-----|----------------|:---------------:|:--------:|:-------------: |4|[Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_4.java) & Python |Hard| Sorting and Searching |10|[Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/backtracking/_10.java) & Python |Hard| Backtracking |11|[Container With Most Water](https://leetcode.com/problems/container-with-most-water/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_11.java) & Python |Medium| Array and Strings |23|[Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/linked_list/_23.java) & Python |Hard| Linked List |41|[First Missing Positive](https://leetcode.com/problems/first-missing-positive/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_41.java) & Python |Hard| Array and Strings |42|[Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/others/_42.java) & Python |Hard| Others |44|[Wildcard Matching](https://leetcode.com/problems/wildcard-matching/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/backtracking/_44.java) & Python |Hard| Backtracking |54|[Spiral Matrix](https://leetcode.com/problems/spiral-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/array_and_string/_54.java) & Python|Medium| Array and Strings |76|[Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_76.java) & Python |Hard| Array and Strings |84|[Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_84.java) & Python |Hard| Others |91|[Decode Ways](https://leetcode.com/problems/decode-ways/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_91.java) & Python |Medium| Dynamic Programming |124|[Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_124.java) & Python |Hard| Trees and Graphs |127|[Word Ladder](https://leetcode.com/problems/word-ladder/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_127.java) & Python |Medium| Trees and Graphs |128|[Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_128.java) & Python |Hard| Array and Strings |130|[Surrounded Regions](https://leetcode.com/problems/surrounded-regions/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_130.java) & Python |Medium| Trees and Graphs |131|[Palindrome Partitioning](https://leetcode.com/problems/palindrome-partitioning/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/backtracking/_131.java) & Python |Medium| Backtracking |135|[Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/linked_list/_135.java) & Python|Medium| Linked List |139|[Word Break](https://leetcode.com/problems/word-break/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_139.java) & Python |Medium| Dynamic Programming |140|[Word Break II](https://leetcode.com/problems/word-break-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_140.java) & Python |Hard| Dynamic Programming |146|[LRU Cache](https://leetcode.com/problems/lru-cache/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/design/_146.java) & Python |Medium| Design |148|[Sort List](https://leetcode.com/problems/sort-list/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/linked_list/_148.java) & Python |Medium| Linked List |149|[Max Points on a Line](https://leetcode.com/problems/max-points-on-a-line/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/math/_149.java) & Python |Hard| Math |152|[Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_152.java) & Python |Medium| Dynamic Programming |179|[Largest Number](https://leetcode.com/problems/largest-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/math/_179.java) & Python |Medium| Math |207|[Course Schedule](https://leetcode.com/problems/course-schedule/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_207.java) & Python |Medium| Trees and Graphs |208|[Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_208.java) & Python |Medium| Design |210|[Course Schedule II](https://leetcode.com/problems/course-schedule-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_210.java) & Python |Medium| Trees and Graphs |212|[Word Search II](https://leetcode.com/problems/word-search-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/trie/_212.java) & Python |Hard| Backtracing |218|[The Skyline Problem](https://leetcode.com/problems/the-skyline-problem/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search_tree/_218.java) & Python |Hard| Others |227|[Basic Calculator II](https://leetcode.com/problems/basic-calculator-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_227.java) & Python |Medium| Array and Strings |236|[Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_tree/_236.java) & Python |Medium| Trees and Graphs |238|[Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_238.java) & Python |Medium| Array and Strings |239|[Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_239.java) & Python |Hard| Array and Strings |279|[Perfect Squares](https://leetcode.com/problems/perfect-squares/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/queue_stack/_279.java) & Python|Medium| Dynamic Programming |287|[Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/binary_search/_287.java) & Python |Medium| Array and Strings |289|[Game of Life](https://leetcode.com/problems/game-of-life/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/array_and_strings/_289.java) & Python |Medium| Array and Strings |295|[Find Median from Data Stream](https://leetcode.com/problems/find-median-from-data-stream/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/design/_295.java) & Python |Hard| Design |301|[Remove Invalid Parentheses](https://leetcode.com/problems/remove-invalid-parentheses/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/backtracking/_301.java) & Python |Hard| Backtracking |309|[Best Time to Buy and Sell Stock with Cooldown](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_309.java) & Python |Medium| Dynamic Programming |312|[Burst Balloons](https://leetcode.com/problems/burst-balloons/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/dynamic_programming/_312.java) & Python |Hard| Dynamic Programming |315|[Count of Smaller Numbers After Self](https://leetcode.com/problems/count-of-smaller-numbers-after-self/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_315.java) & Python |Hard| Trees and Graphs |324|[Wiggle Sort II](https://leetcode.com/problems/wiggle-sort-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/sorting_and_searching/_324.java) & Python |Medium| Sorting and Searching |329|[Longest Increasing Path in a Matrix](https://leetcode.com/problems/longest-increasing-path-in-a-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_329.java) & Python |Hard| Trees and Graphs |341|[Flatten Nested List Iterator](https://leetcode.com/problems/flatten-nested-list-iterator/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/design/_341.java) & Python |Medium| Design |378|[Kth Smallest Element in a Sorted Matrix](https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/sorting_and_searching/_378.java) & Python |Medium| Sorting and Searching |406|[Queue Reconstruction by Height](https://leetcode.com/problems/queue-reconstruction-by-height/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/others/_406.java) & Python |Medium| Others |454|[4Sum II](https://leetcode.com/problems/4sum-ii/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/learn/hash_table/_454.java) & Python |Medium| Array and Strings |547|[Friend Circles](https://leetcode.com/problems/friend-circles/description/)|[Java](https://github.com/guobinhit/myleetcode/blob/master/codes/java/leetcodes/src/main/java/com/hit/basmath/interview/top_interview_questions/hard_collection/trees_and_graphs/_547.java) & Python |Medium| Trees and Graphs ------------ - [↑↑↑ RETURN THE TOP ↑↑↑](#index)