# leetcode

**Repository Path**: laoli2020/leetcode

## Basic Information

- **Project Name**: leetcode
- **Description**: 😏 LeetCode solutions in any programming language | 多种编程语言实现 LeetCode、《剑指 Offer（第 2 版）》、《程序员面试金典（第 6 版）》题解
- **Primary Language**: Java
- **License**: CC-BY-SA-4.0
- **Default Branch**: main
- **Homepage**: https://github.com/doocs/leetcode
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 342
- **Created**: 2021-09-25
- **Last Updated**: 2021-09-25

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

<p align="center">
  <a href="https://github.com/doocs/leetcode"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/leetcode-doocs.png" alt="LeetCode-GitHub-Doocs"></a>
</p>

<p align="center">
  <a href="https://github.com/doocs/leetcode"><img src="https://img.shields.io/badge/langs-Java%20%7C%20Python%20%7C%20C%2B%2B%20%7C%20JavaScript%20%7C%20Go%20%7C%20...-red?style=flat-square&color=42b883" alt="languages"></a>
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</p>

## Introduction

Complete solutions to [LeetCode](https://leetcode.com/problemset/all/), [LCOF](https://leetcode-cn.com/problemset/lcof/) and [LCCI](https://leetcode-cn.com/problemset/lcci/) problems, updated daily. Please give me a [star](https://github.com/doocs/leetcode) 🌟 if you like it.

[中文文档](./README.md)

## Sites

- Netlify: https://lc.netlify.app
- Gitee Pages: https://doocs.gitee.io/leetcode
- GitHub Pages: https://doocs.github.io/leetcode

## Solutions

- [LeetCode](./solution/README_EN.md)
- [LCOF: Coding Interviews, 2nd Edition](/lcof/README_EN.md)
- [LCCI: Cracking the Coding Interview, 6th Edition](./lcci/README_EN.md)

## Basic Algorithms

### Sorting

- [Bubble Sort](./basic/sorting/BubbleSort/README.md)
- [Insertion Sort](./basic/sorting/InsertionSort/README.md)
- [Selection Sort](./basic/sorting/SelectionSort/README.md)
- [Merge Sort(Algorithm Template)](./basic/sorting/MergeSort/README.md)
- [Quick Sort(Algorithm Template)](./basic/sorting/QuickSort/README.md)
- [Shell Sort](./basic/sorting/ShellSort/README.md)
- [Heap Sort(Algorithm Template)](./basic/sorting/HeapSort/README.md)

### Searching

- [Binary Search(Algorithm Template)](./basic/searching/BinarySearch/README_EN.md)

## High Frequency Interview Questions

### Arrays

- [Majority Element](./solution/0100-0199/0169.Majority%20Element/README_EN.md)
- [Remove Duplicates from Sorted Array](./solution/0000-0099/0026.Remove%20Duplicates%20from%20Sorted%20Array/README_EN.md)
- [Remove Duplicates from Sorted Array II](./solution/0000-0099/0080.Remove%20Duplicates%20from%20Sorted%20Array%20II/README_EN.md)
- [Remove Element](./solution/0000-0099/0027.Remove%20Element/README_EN.md)
- [Move Zeroes](./solution/0200-0299/0283.Move%20Zeroes/README_EN.md)
- [Rotate Array](./solution/0100-0199/0189.Rotate%20Array/README_EN.md)
- [Spiral Matrix](./solution/0000-0099/0054.Spiral%20Matrix/README_EN.md)
- [Two Sum](./solution/0000-0099/0001.Two%20Sum/README_EN.md)
- [3Sum](./solution/0000-0099/0015.3Sum/README_EN.md)
- [4Sum](./solution/0000-0099/0018.4Sum/README_EN.md)
- [3Sum Smaller](./solution/0200-0299/0259.3Sum%20Smaller/README_EN.md)
- [3Sum Closest](./solution/0000-0099/0016.3Sum%20Closest/README_EN.md)
- [Merge Sorted Array](./solution/0000-0099/0088.Merge%20Sorted%20Array/README_EN.md)
- [Find Minimum in Rotated Sorted Array](./solution/0100-0199/0153.Find%20Minimum%20in%20Rotated%20Sorted%20Array/README_EN.md)
- [Find Minimum in Rotated Sorted Array II](./solution/0100-0199/0154.Find%20Minimum%20in%20Rotated%20Sorted%20Array%20II/README_EN.md)
- [Product of Array Except Self](./solution/0200-0299/0238.Product%20of%20Array%20Except%20Self/README_EN.md)

### Strings

- [Longest Substring Without Repeating Characters](./solution/0000-0099/0003.Longest%20Substring%20Without%20Repeating%20Characters/README_EN.md)
- [Longest Common Prefix](./solution/0000-0099/0014.Longest%20Common%20Prefix/README_EN.md)
- [Reverse Vowels of a String](./solution/0300-0399/0345.Reverse%20Vowels%20of%20a%20String/README_EN.md)
- [String to Integer (atoi)](./solution/0000-0099/0008.String%20to%20Integer%20%28atoi%29/README_EN.md)
- [Ransom Note](./solution/0300-0399/0383.Ransom%20Note/README_EN.md)

### Linked List

- [Add Two Numbers](./solution/0000-0099/0002.Add%20Two%20Numbers/README_EN.md)
- [Add Two Numbers II](./solution/0400-0499/0445.Add%20Two%20Numbers%20II/README_EN.md)
- [Delete Node in a Linked List](./solution/0200-0299/0237.Delete%20Node%20in%20a%20Linked%20List/README_EN.md)
- [Remove Duplicates from Sorted List](./solution/0000-0099/0083.Remove%20Duplicates%20from%20Sorted%20List/README_EN.md)
- [Remove Duplicates from Sorted List II](./solution/0000-0099/0082.Remove%20Duplicates%20from%20Sorted%20List%20II/README_EN.md)
- [Remove Linked List Elements](./solution/0200-0299/0203.Remove%20Linked%20List%20Elements/README_EN.md)
- [Kth Node From End of List](./lcci/02.02.Kth%20Node%20From%20End%20of%20List/README_EN.md)
- [Swap Nodes in Pairs](./solution/0000-0099/0024.Swap%20Nodes%20in%20Pairs/README_EN.md)
- [Merge Two Sorted Lists](./solution/0000-0099/0021.Merge%20Two%20Sorted%20Lists/README_EN.md)
- [Merge k Sorted Lists](./solution/0000-0099/0023.Merge%20k%20Sorted%20Lists/README_EN.md)
- [Insertion Sort List](./solution/0100-0199/0147.Insertion%20Sort%20List/README_EN.md)
- [Sort List](./solution/0100-0199/0148.Sort%20List/README_EN.md)
- [Reverse Linked List](./solution/0200-0299/0206.Reverse%20Linked%20List/README_EN.md)
- [Reverse Linked List II](./solution/0000-0099/0092.Reverse%20Linked%20List%20II/README_EN.md)
- [Reorder List](./solution/0100-0199/0143.Reorder%20List/README_EN.md)
- [Rotate List](./solution/0000-0099/0061.Rotate%20List/README_EN.md)
- [Palindrome Linked List](./solution/0200-0299/0234.Palindrome%20Linked%20List/README_EN.md)
- [Intersection of Two Linked Lists](./solution/0100-0199/0160.Intersection%20of%20Two%20Linked%20Lists/README_EN.md)
- [Odd Even Linked List](./solution/0300-0399/0328.Odd%20Even%20Linked%20List/README_EN.md)
- [Linked List Cycle](./solution/0100-0199/0141.Linked%20List%20Cycle/README_EN.md)
- [Linked List Cycle II](./solution/0100-0199/0142.Linked%20List%20Cycle%20II/README_EN.md)
- [Design Linked List](./solution/0700-0799/0707.Design%20Linked%20List/README_EN.md)

### Binary Tree

- [Binary Tree Preorder Traversal](./solution/0100-0199/0144.Binary%20Tree%20Preorder%20Traversal/README_EN.md)
- [Binary Tree Postorder Traversal](./solution/0100-0199/0145.Binary%20Tree%20Postorder%20Traversal/README_EN.md)
- [Binary Tree Inorder Traversal](./solution/0000-0099/0094.Binary%20Tree%20Inorder%20Traversal/README_EN.md)
- [Symmetric Tree](./solution/0100-0199/0101.Symmetric%20Tree/README_EN.md)
- [Invert Binary Tree](./solution/0200-0299/0226.Invert%20Binary%20Tree/README_EN.md)
- [Binary Tree Level Order Traversal](./solution/0100-0199/0102.Binary%20Tree%20Level%20Order%20Traversal/README_EN.md)
- [Binary Tree Level Order Traversal II](./solution/0100-0199/0107.Binary%20Tree%20Level%20Order%20Traversal%20II/README_EN.md)
- [Binary Tree Right Side View](./solution/0100-0199/0199.Binary%20Tree%20Right%20Side%20View/README_EN.md)
- [Maximum Depth of Binary Tree](./solution/0100-0199/0104.Maximum%20Depth%20of%20Binary%20Tree/README_EN.md)
- [Minimum Depth of Binary Tree](./solution/0100-0199/0111.Minimum%20Depth%20of%20Binary%20Tree/README_EN.md)
- [Binary Tree Paths](./solution/0200-0299/0257.Binary%20Tree%20Paths/README_EN.md)
- [Path Sum](./solution/0100-0199/0112.Path%20Sum/README_EN.md)
- [Path Sum II](./solution/0100-0199/0113.Path%20Sum%20II/README_EN.md)
- [Construct Binary Tree from Preorder and Inorder Traversal](./solution/0100-0199/0105.Construct%20Binary%20Tree%20from%20Preorder%20and%20Inorder%20Traversal/README_EN.md)
- [Construct Binary Tree from Inorder and Postorder Traversal](./solution/0100-0199/0106.Construct%20Binary%20Tree%20from%20Inorder%20and%20Postorder%20Traversal/README_EN.md)
- [Binary Search Tree Iterator](./solution/0100-0199/0173.Binary%20Search%20Tree%20Iterator/README_EN.md)
- [Lowest Common Ancestor of a Binary Tree](./solution/0200-0299/0236.Lowest%20Common%20Ancestor%20of%20a%20Binary%20Tree/README_EN.md)
- [Lowest Common Ancestor of a Binary Search Tree](./solution/0200-0299/0235.Lowest%20Common%20Ancestor%20of%20a%20Binary%20Search%20Tree/README_EN.md)
- [BiNode](./lcci/17.12.BiNode/README_EN.md)
- [Convert Binary Search Tree to Sorted Doubly Linked List](./solution/0400-0499/0426.Convert%20Binary%20Search%20Tree%20to%20Sorted%20Doubly%20Linked%20List/README_EN.md)
- [Boundary of Binary Tree](./solution/0500-0599/0545.Boundary%20of%20Binary%20Tree/README_EN.md)
- [Populating Next Right Pointers in Each Node](./solution/0100-0199/0116.Populating%20Next%20Right%20Pointers%20in%20Each%20Node/README_EN.md)
- [Populating Next Right Pointers in Each Node II](./solution/0100-0199/0117.Populating%20Next%20Right%20Pointers%20in%20Each%20Node%20II/README_EN.md)

### Math

- [Integer to Roman](./solution/0000-0099/0012.Integer%20to%20Roman/README_EN.md)
- [Roman to Integer](./solution/0000-0099/0013.Roman%20to%20Integer/README_EN.md)
- [Single Number](./solution/0100-0199/0136.Single%20Number/README_EN.md)
- [Single Number II](./solution/0100-0199/0137.Single%20Number%20II/README_EN.md)
- [Single Number III](./solution/0200-0299/0260.Single%20Number%20III/README_EN.md)
- [Set Mismatch](./solution/0600-0699/0645.Set%20Mismatch/README_EN.md)
- [Number of 1 Bits](./solution/0100-0199/0191.Number%20of%201%20Bits/README_EN.md)
- [Count Primes](./solution/0200-0299/0204.Count%20Primes/README_EN.md)
- [Missing Number](./solution/0200-0299/0268.Missing%20Number/README_EN.md)

### Stack & Queue

- [Valid Parentheses](./solution/0000-0099/0020.Valid%20Parentheses/README_EN.md)
- [Min Stack](./solution/0100-0199/0155.Min%20Stack/README_EN.md)
- [Implement Queue using Stacks](./solution/0200-0299/0232.Implement%20Queue%20using%20Stacks/README_EN.md)
- [Implement Stack using Queues](./solution/0200-0299/0225.Implement%20Stack%20using%20Queues/README_EN.md)
- [Evaluate Reverse Polish Notation](./solution/0100-0199/0150.Evaluate%20Reverse%20Polish%20Notation/README_EN.md)
- [Number of Recent Calls](./solution/0900-0999/0933.Number%20of%20Recent%20Calls/README_EN.md)
- [Daily Temperatures](./solution/0700-0799/0739.Daily%20Temperatures/README_EN.md)
- [Basic Calculator II](./solution/0200-0299/0227.Basic%20Calculator%20II/README_EN.md)
- [Next Greater Element I](./solution/0400-0499/0496.Next%20Greater%20Element%20I/README_EN.md)
- [Next Greater Element II](./solution/0500-0599/0503.Next%20Greater%20Element%20II/README_EN.md)

### Dynamic Programming

- [Fibonacci Number](./solution/0500-0599/0509.Fibonacci%20Number/README_EN.md)
- [N-th Tribonacci Number](./solution/1100-1199/1137.N-th%20Tribonacci%20Number/README_EN.md)
- [Climbing Stairs](./solution/0000-0099/0070.Climbing%20Stairs/README_EN.md)
- [Min Cost Climbing Stairs](./solution/0700-0799/0746.Min%20Cost%20Climbing%20Stairs/README_EN.md)
- [House Robber](./solution/0100-0199/0198.House%20Robber/README_EN.md)
- [House Robber II](./solution/0200-0299/0213.House%20Robber%20II/README_EN.md)
- [Delete and Earn](./solution/0700-0799/0740.Delete%20and%20Earn/README_EN.md)
- [Jump Game](./solution/0000-0099/0055.Jump%20Game/README_EN.md)
- [Jump Game II](./solution/0000-0099/0045.Jump%20Game%20II/README_EN.md)
- [Maximum Subarray](./solution/0000-0099/0053.Maximum%20Subarray/README_EN.md)
- [Maximum Sum Circular Subarray](./solution/0900-0999/0918.Maximum%20Sum%20Circular%20Subarray/README_EN.md)
- [Maximum Product Subarray](./solution/0100-0199/0152.Maximum%20Product%20Subarray/README_EN.md)
- [Maximum Length of Subarray With Positive Product](./solution/1500-1599/1567.Maximum%20Length%20of%20Subarray%20With%20Positive%20Product/README_EN.md)
- [Best Sightseeing Pair](./solution/1000-1099/1014.Best%20Sightseeing%20Pair/README_EN.md)
- [Best Time to Buy and Sell Stock](./solution/0100-0199/0121.Best%20Time%20to%20Buy%20and%20Sell%20Stock/README_EN.md)
- [Best Time to Buy and Sell Stock II](./solution/0100-0199/0122.Best%20Time%20to%20Buy%20and%20Sell%20Stock%20II/README_EN.md)
- [Best Time to Buy and Sell Stock III](./solution/0100-0199/0123.Best%20Time%20to%20Buy%20and%20Sell%20Stock%20III/README_EN.md)
- [Best Time to Buy and Sell Stock with Cooldown](./solution/0300-0399/0309.Best%20Time%20to%20Buy%20and%20Sell%20Stock%20with%20Cooldown/README_EN.md)
- [Best Time to Buy and Sell Stock with Transaction Fee](./solution/0700-0799/0714.Best%20Time%20to%20Buy%20and%20Sell%20Stock%20with%20Transaction%20Fee/README_EN.md)
- [Word Break](./solution/0100-0199/0139.Word%20Break/README_EN.md)
- [Trapping Rain Water](./solution/0000-0099/0042.Trapping%20Rain%20Water/README_EN.md)
- [Arithmetic Slices](./solution/0400-0499/0413.Arithmetic%20Slices/README_EN.md)
- [Decode Ways](./solution/0000-0099/0091.Decode%20Ways/README_EN.md)
- [Unique Binary Search Trees](./solution/0000-0099/0096.Unique%20Binary%20Search%20Trees/README_EN.md)
- [Ugly Number II](./solution/0200-0299/0264.Ugly%20Number%20II/README_EN.md)
- [Pascal's Triangle](./solution/0100-0199/0118.Pascal%27s%20Triangle/README_EN.md)
- [Pascal's Triangle II](./solution/0100-0199/0119.Pascal%27s%20Triangle%20II/README_EN.md)
- [Minimum Falling Path Sum](./solution/0900-0999/0931.Minimum%20Falling%20Path%20Sum/README_EN.md)
- [Triangle](./solution/0100-0199/0120.Triangle/README_EN.md)
- [Matrix Block Sum](./solution/1300-1399/1314.Matrix%20Block%20Sum/README_EN.md)
- [Range Sum Query 2D - Immutable](./solution/0300-0399/0304.Range%20Sum%20Query%202D%20-%20Immutable/README_EN.md)
- [Unique Paths](./solution/0000-0099/0062.Unique%20Paths/README_EN.md)
- [Unique Paths II](./solution/0000-0099/0063.Unique%20Paths%20II/README_EN.md)
- [Minimum Path Sum](./solution/0000-0099/0064.Minimum%20Path%20Sum/README_EN.md)
- [Longest Palindromic Substring](./solution/0000-0099/0005.Longest%20Palindromic%20Substring/README_EN.md)
- [Longest Palindromic Subsequence](.solution/0500-0599/0516.Longest%20Palindromic%20Subsequence/README_EN.md)
- [Longest Increasing Subsequence](./solution/0300-0399/0300.Longest%20Increasing%20Subsequence/README_EN.md)
- [Wiggle Subsequence](./solution/0300-0399/0376.Wiggle%20Subsequence/README_EN.md)
- [Longest Common Subsequence](./solution/1100-1199/1143.Longest%20Common%20Subsequence/README_EN.md)
- [Edit Distance](./solution/0000-0099/0072.Edit%20Distance/README_EN.md)
- [Coin Change](./solution/0300-0399/0322.Coin%20Change/README_EN.md)
- [Coin Change 2](./solution/0500-0599/0518.Coin%20Change%202/README_EN.md)
- [Combination Sum IV](./solution/0300-0399/0377.Combination%20Sum%20IV/README_EN.md)
- [Integer Break](./solution/0300-0399/0343.Integer%20Break/README_EN.md)
- [Perfect Squares](./solution/0200-0299/0279.Perfect%20Squares/README_EN.md)
- [Russian Doll Envelopes](./solution/0300-0399/0354.Russian%20Doll%20Envelopes/README_EN.md)

### Backtracking

- [Subsets](./solution/0000-0099/0078.Subsets/README_EN.md)
- [Subsets II](./solution/0000-0099/0090.Subsets%20II/README_EN.md)

### Design

- [LRU Cache](./solution/0100-0199/0146.Lru%20Cache/README_EN.md)
- [Implement Trie (Prefix Tree)](<solution/0200-0299/0208.Implement%20Trie%20(Prefix%20Tree)/README_EN.md>)
- [Implement Trie II (Prefix Tree)](./solution/1800-1899/1804.Implement%20Trie%20II%20%28Prefix%20Tree%29/README_EN.md)
- [Design Circular Queue](./solution/0600-0699/0622.Design%20Circular%20Queue/README_EN.md)
- [Design Circular Deque](./solution/0600-0699/0641.Design%20Circular%20Deque/README_EN.md)
- [Design HashSet](./solution/0700-0799/0705.Design%20HashSet/README_EN.md)
- [Design HashMap](./solution/0700-0799/0706.Design%20HashMap/README_EN.md)

### Database

- [Combine Two Tables](./solution/0100-0199/0175.Combine%20Two%20Tables/README_EN.md)
- [Second Highest Salary](./solution/0100-0199/0176.Second%20Highest%20Salary/README_EN.md)
- [Nth Highest Salary](./solution/0100-0199/0177.Nth%20Highest%20Salary/README_EN.md)
- [Rank Scores](./solution/0100-0199/0178.Rank%20Scores/README_EN.md)

## Maintainer

- [Yang Libin](https://github.com/yanglbme)
- [Mao Longlong](https://github.com/MaoLongLong)

## Contributions

I'm looking for long-term contributors/partners to this repo! Send me [PRs](https://github.com/doocs/leetcode/pulls) if you're interested! See the following:

1. Fork [this repository](https://github.com/doocs/leetcode) to your own GitHub account and then clone it to your local machine.
1. Make some changes to your leetcode repository, then push the changes to your remote GitHub repository.
1. Create a pull request with your changes!
1. See [CONTRIBUTING](https://github.com/doocs/.github/blob/main/CONTRIBUTING.md) or [GitHub Help](https://help.github.com/en) for more details.

<p align="center">
  <a href="https://github.com/doocs/leetcode"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/how-to-contribute.png" alt="How to contribute"></a>
</p>

You can also contribute to [doocs/leetcode](https://github.com/doocs/leetcode) using [Gitpod.io](https://www.gitpod.io), a free online dev environment with a single click.

<a href="https://gitpod.io/#https://github.com/doocs/leetcode" target="_blank" alt="Open in Gitpod"><img src="https://gitpod.io/button/open-in-gitpod.svg"></a>

## Contributors

This project exists thanks to all the people who contribute.

<a href="https://github.com/doocs/leetcode/graphs/contributors" target="_blank"><img src="./images/contributors.svg" /></a>

## Backers & Sponsors

Thank you to all our backers and sponsors!

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> "_You help the developer community practice for interviews, and there is nothing better we could ask for._" -- [Alan Yessenbayev](https://opencollective.com/alan-yessenbayev)

## License

This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike 4.0 International License</a>.