LeetCode刷题

题号是LeetCode原题，题目是自己的解答

Easy

题号	题目	Tags	star
1	Two Sum	HashMap	⭐ ⭐ ⭐
7	Reverse Integer	Integer	⭐ ⭐
14	Longest Common Prefix	String	⭐
20	Valid Parentheses	String、Stack	⭐ ⭐ ⭐
21	Merge Two Sorted Lists	LinkedList	⭐ ⭐ ⭐
53	Maximum Subarray	Array、DP	⭐ ⭐ ⭐ ⭐
88	Merge Sorted Array	Array、双指针
100	Same Tree	Tree	⭐ ⭐ ⭐
101	Symmetric Tree	Tree	⭐ ⭐ ⭐
104	Maximum Depth of Binary Tree	Tree	⭐ ⭐ ⭐
105	Construct Binary Tree from Preorder and Inorder Traversal	Tree	⭐ ⭐ ⭐
108	Convert Sorted Array to Binary Search Tree	Tree	⭐ ⭐ ⭐
111	Minimum Depth of Binary Tree	Tree、递归	⭐ ⭐ ⭐
112	Path Sum	Tree	⭐ ⭐
115	Min Stack	Stack	⭐ ⭐ ⭐
119	Pascal's Triangle II	Array	⭐ ⭐
120	Triangle	DP	⭐ ⭐ ⭐
121	Best Time to Buy and Sell Stock	DP	⭐ ⭐ ⭐
122	Best Time to Buy and Sell Stock II	DP	⭐
136	Single Number	Array、二进制	⭐ ⭐ ⭐
141	Linked List Cycle	LinkedList、双指针	⭐ ⭐ ⭐
148	Sort List	LinkedList、MergeSort	⭐ ⭐ ⭐
160	Intersection of Two Linked Lists	LinkedList、双指针	⭐ ⭐ ⭐
169	Majority Element	Array	⭐ ⭐
198	House Robber	Array、DP	⭐ ⭐ ⭐
200	Number of Islands	DFS、BFS	⭐ ⭐ ⭐
206	Reverse Linked List	ListNode	⭐ ⭐ ⭐
207	Course Schedule	DFS、BFS	⭐ ⭐ ⭐
217	Contains Duplicate	Array、HashTable	⭐
226	Invert Binary Tree	Tree	⭐ ⭐ ⭐
234	Palindrome Linked List	LinkedList、双指针	⭐ ⭐ ⭐
338	Counting Bits	bits	⭐ ⭐ ⭐
401	Binary Watch	递归	⭐
437	Path Sum III	HashMap,Tree	⭐ ⭐ ⭐
448	Find All Numbers Disappeared in an Array	Array	⭐ ⭐ ⭐
461	Hamming Distance	bits	⭐ ⭐ ⭐
538	Convert BST to Greater Tree	二叉搜索树	⭐ ⭐ ⭐
543	Diameter of Binary Tree	Tree、递归	⭐ ⭐ ⭐
572	Subtree of Another Tree	Tree	⭐ ⭐ ⭐
581	Shortest Unsorted Continuous Subarray	Array	⭐ ⭐ ⭐
617	Merge Two Binary Trees	Tree	⭐ ⭐ ⭐
628	Maximum Product of Three Numbers	Array	⭐
771	Jewels and Stones	String	⭐

Medium

题号	题目	Tags	star
2	Add Two Numbers	LinkedList	⭐ ⭐ ⭐
3	Longest Substring Without Repeating Characters	双指针	⭐ ⭐ ⭐
5	Longest Palindromic Substring	String、动态规划	⭐ ⭐ ⭐
6	ZigZag Conversion	String	⭐
15	3Sum	Array、双指针	⭐ ⭐ ⭐
17	Letter Combinations of a Phone Number	递归	⭐ ⭐ ⭐
19	Remove Nth Node From End of List	双指针	⭐ ⭐ ⭐
22	Generate Parentheses	String、回溯法	⭐ ⭐ ⭐
24	Swap Nodes in Pairs	LinkedList	⭐ ⭐ ⭐
34	Find First and Last Position of Element in Sorted Array	Array、BinarySearch	⭐ ⭐ ⭐
39	CombinationSum	Array、回溯法	⭐ ⭐ ⭐
40	CombinationSum	Array、回溯法	⭐ ⭐ ⭐
46	Permutations	回溯法	⭐ ⭐ ⭐
47	PermutationsII	回溯法	⭐ ⭐ ⭐
48	Rotate Image	二维数组	⭐ ⭐
49	Group Anagrams	ArrayList, HashMap	⭐ ⭐ ⭐
56	Merge Intervals	迭代器，自写比较函数	⭐ ⭐ ⭐
60	Permutation Sequence	Array、感觉像是递归
61	Rotate List	LinkedList、双指针	⭐
62	Unique Paths	二维数组、动态规划	⭐ ⭐ ⭐
63	Unique Paths II	二维数组、动态规划	⭐ ⭐ ⭐
64	Minimum Path Sum	二维数组、动态规划	⭐ ⭐ ⭐
74	Search a 2D Matrix	二分查找	⭐ ⭐
77	Combinations	回溯法	⭐ ⭐ ⭐
78	Subsets	Array、回溯法	⭐ ⭐ ⭐
79	Word Search	二维数组、递归	⭐ ⭐ ⭐
80	Remove Duplicates from Sorted Array II	Array、双指针
86	Partition List	LinkedList、双指针
90	SubsetsII	Array、回溯法	⭐ ⭐ ⭐
92	Reverse Linked List II	LinkedList	⭐ ⭐ ⭐
94	Binary Tree Inorder Traversal	Tree	⭐ ⭐ ⭐
96	Unique Binary Search Trees	BST, 递归	⭐ ⭐ ⭐
102	Binary Tree Level Order Traversal	Tree	⭐ ⭐ ⭐
103	Binary Tree Zigzag Level Order Traversal	Tree	⭐ ⭐ ⭐
113	Path Sum II	Tree	⭐ ⭐
114	Flatten Binary Tree to Linked List	Tree	⭐ ⭐ ⭐
120	Triangle	DP	⭐ ⭐ ⭐
139	Word Break	DP	⭐ ⭐ ⭐
142	Linked List Cycle II	LinkedList、双指针	⭐ ⭐ ⭐
143	Reorder List	LinkedList	⭐ ⭐ ⭐
152	Maximum Product Subarray	Array、 DP	⭐ ⭐ ⭐
209	Minimum Size Subarray Sum	Array、滑动窗口
213	House Robber II	动态规划	⭐ ⭐
215	Kth Largest Element in an Array	Array、快速选择算法	⭐ ⭐ ⭐ ⭐
216	CombinationSumIII	Array、回溯法	⭐ ⭐ ⭐
221	Maximal Square	DP	⭐ ⭐ ⭐
238	Product of Array Except Self	Array
240	Search a 2D Matrix II		⭐ ⭐ ⭐
264	Ugly NumberII	DP	⭐ ⭐
279	Perfect Squares	DP	⭐ ⭐ ⭐
287	Find the Duplicate Number	Array、双指针	⭐ ⭐ ⭐
300	Longest Increasing Subsequence	DP、Binary Search	⭐ ⭐ ⭐
309	Best Time to Buy and Sell Stock with Cooldown	DP、状态机	⭐ ⭐ ⭐
334	Increasing Triplet Subsequence		⭐ ⭐
337	House Robber III	HashMap、DP	⭐ ⭐ ⭐
347	Top K Frequent Elements	HashMap	⭐ ⭐ ⭐
357	Count Numbers with Unique Digits	DP、回溯	⭐ ⭐ ⭐
438	Find All Anagrams in a String	HashTable、滑动窗口	⭐ ⭐ ⭐
442	Find All Duplicates in an Array	Array	⭐ ⭐ ⭐
526	BeautifulArrangement	回溯	⭐ ⭐ ⭐
560	Subarray Sum Equals K	Array、HashMap	⭐ ⭐ ⭐
646	Maximum Length of Pair Chain	DP、Greedy	⭐ ⭐ ⭐
673	Number of Longest Increasing Subsequence	DP	⭐ ⭐
713	Subarray Product Less Than K	双指针、滑动窗口	⭐ ⭐
714	Best Time to Buy and Sell Stock with Transaction Fee	动态规划、状态机	⭐ ⭐ ⭐

Hard

题号	题目	Tags	star
4	Median of Two Sorted Arrays	分治思想、二分查找	⭐ ⭐ ⭐
123	Best Time to Buy and Sell Stock III	DP、状态机	⭐ ⭐ ⭐
188	Best Time to Buy and Sell Stock IV	DP	⭐ ⭐ ⭐