Introduction

Complete solutions to Leetcode problems, updated daily.

Solution List

Easy

#	Title	Tags
001	Two Sum	Array, Hash Table
007	Reverse Integer	Math
009	Palindrome Number	Math
013	Roman to Integer	Math, String
014	Longest Common Prefix	String
020	Valid Parentheses	String, Stack
021	Merge Two Sorted Lists	Linked List
053	Maximum Subarray	Array, Divide and Conquer, Dynamic Programming
070	Climbing Stairs	Dynamic Programming
083	Remove Duplicates from Sorted List	Linked List
136	Single Number	Hash Table, Bit Manipulation
189	Rotate Array	Array
198	House Robber	Dynamic Programming
203	Remove Linked List Elements	Linked List
231	Power of Two	Math, Bit Manipulation
235	Lowest Common Ancestor of a Binary Search Tree	Tree
237	Delete Node in a Linked List	Linked List
344	Reverse String	Two Pointers, String
703	Kth Largest Element in a Stream	Heap
876	Middle of the Linked List	Linked List

Medium

#	Title	Tags
002	Add Two Numbers	Linked List, Math
015	3Sum	Array, Two Pointers
019	Remove Nth Node From End of List	Linked List, Two Pointers
024	Swap Nodes in Pairs	Linked List
031	Next Permutation	Array
046	Permutations	Backtracking
047	Permutations II	Backtracking
062	Unique Paths	Array, Dynamic Programming
063	Unique Paths II	Array, Dynamic Programming
075	Sort Colors	Array, Two Pointers, Sort
082	Remove Duplicates from Sorted List II	Linked List
086	Partition List	Linked List, Two Pointers
092	Reverse Linked List II	Linked List
094	Binary Tree Inorder Traversal	Hash Table, Stack, Tree
102	Binary Tree Level Order Traversal	Tree, Breadth-first Search
127	Word Ladder	Breadth-first Search
130	Surrounded Regions	Depth-first Search, Breadth-first Search, Union Find
137	Single Number II	Bit Manipulation
144	Binary Tree Preorder Traversal	Stack, Tree
150	Evaluate Reverse Polish Notation	Stack
153	Find Minimum in Rotated Sorted Array	Array, Binary Search

Hard

#	Title	Tags
023	Merge k Sorted Lists	Linked List, Divide and Conquer, Heap
032	Longest Valid Parentheses	String, Dynamic Programming
084	Largest Rectangle in Histogram	Array, Stack
145	Binary Tree Postorder Traversal	Stack, Tree
295	Find Median from Data Stream	Heap, Design

Contributions

I'm looking for long-term contributors/partners to this repo! Send me PRs if you're interested! See the following:

• Fork this repository to your own GitHub account and then clone it to your local device.
• Submit a pull request with your changes!

Contributors

yanglbme 💻	chakyam 💻	zhkmxx9302013 💻	MarkKuang1991 💻