编号序

Done	No.	Title	Difficulty	Tag	Mark
✅	1	Two Sum	Easy
✅	2	Add Two Numbers	Medium
✅	3	Longest Substring Without Repeating Characters	Medium
✅	4	Median of Two Sorted Arrays	Hard		hot
✅	5	Longest Palindromic Substring	Medium
✅	7	Reverse Integer	Medium
⬜	8	String to Integer (atoi)	Medium
✅	10	Regular Expression Matching	Hard		hot
✅	11	Container With Most Water	Medium
✅	12	Integer to Roman	Medium
✅	13	Roman to Integer	Easy
✅	14	Longest Common Prefix	Easy
✅	15	3Sum	Medium
✅	16	3Sum Closest	Medium
✅	17	Letter Combinations of a Phone Number	Medium
✅	19	Remove Nth Node From End of List	Easy
✅	20	Valid Parentheses	Easy
✅	21	Merge Two Sorted Lists	Easy
✅	22	Generate Parentheses	Medium
✅	23	Merge k Sorted Lists	Hard		hot
✅	24	Swap Nodes in Pairs	Medium
✅	25	Reverse Nodes in k-Group	Hard		hot
✅	26	Remove Duplicates from Sorted Array	Easy
⬜	28	Implement strStr()	Medium
⬜	29	Divide Two Integers	Medium
✅	30	Substring with Concatenation of All Words	Hard		hot
✅	31	Next Permutation	Medium
✅	32	Longest Valid Parentheses	Hard		hot
✅	33	Search in Rotated Sorted Array	Medium
✅	34	Search for a Range	Medium
✅	35	Search Insert Position	Medium
✅	36	isValidSudoku	Medium
✅	37	Sudoku Solver	Hard		hot
✅	39	Combination Sum	Medium
✅	40	Combination Sum II	Medium
✅	41	First Missing Positive	Hard		hot
✅	42	Trapping Rain Water	Hard		hot
✅	43	Multiply Strings	Medium
✅	44	Wildcard Matching	Hard		hot
✅	45	Jump Game II	Medium
✅	46	Permutations	Medium
✅	47	Permutations II	Medium
✅	48	Rotate Image	Medium
⬜	50	Pow(x, n)	Medium
✅	51	N-Queens	Hard		hot
✅	52	N-Queens II	Hard		hot
✅	53	Maximum Subarray	Medium
✅	54	Spiral Matrix	Medium
✅	55	Jump Game	Medium
✅	56	Merge Intervals	Medium
✅	60	Permutation Sequence	Hard		hot
✅	62	Unique Paths	Medium
✅	63	Unique Paths II	Medium
✅	64	Minimum Path Sum	Medium
✅	65	Valid Number	Hard		hot
✅	66	Plus One	Easy
✅	68	Text Justification	Hard		hot
⬜	69	Sqrt(x)	Medium
✅	70	Climbing Stairs	Easy
✅	72	Edit Distance	Hard		hot
✅	74	Search a 2D Matrix	Medium
✅	76	Minimum Window Substring	Hard		hot
✅	77	Combinations	Medium
✅	78	Subsets	Medium
✅	79	Word Search	Medium
✅	81	Search in Rotated Sorted Array II	Medium
✅	82	Remove Duplicates from Sorted List II	Medium
✅	83	Remove Duplicates from Sorted List	Easy
✅	84	Largest Rectangle in Histogram	Hard		hot
✅	85	Maximal Rectangle	Hard		hot
✅	86	Partition List	Medium
✅	87	Scramble String	Hard		hot
✅	88	Merge Sorted Array	Easy
✅	90	Subsets II	Medium
✅	91	Decode Ways	Medium
✅	92	Reverse Linked List II	Medium
✅	93	Restore IP Addresses	Medium
✅	94	Binary Tree Inorder Traversal	Medium
✅	95	Unique Binary Search Trees II	Medium
✅	97	Interleaving String	Medium
✅	98	Validate Binary Search Tree	Medium
✅	99	Recover Binary Search Tree	Medium
✅	100	Same Tree	Easy
✅	101	Symmetric Tree	Medium
✅	102	Binary Tree Level Order Traversal	Easy
✅	103	Binary Tree Zigzag Level Order Traversal	Medium
✅	104	Maximum Depth of Binary Tree	Easy
✅	105	Construct Binary Tree from Preorder and Inorder Traversal	Medium
✅	106	Construct Binary Tree from Inorder and Postorder Traversal	Medium
✅	107	Binary Tree Level Order Traversal II	Easy
✅	108	Convert Sorted Array to Binary Search Tree	Medium
✅	109	Convert Sorted List to Binary Search Tree	Medium
✅	110	Balanced Binary Tree	Easy
✅	111	Minimum Depth of Binary Tree	Medium
✅	112	Path Sum	Easy
✅	113	Path Sum II	Medium
✅	114	Flatten Binary Tree to Linked List	Medium
✅	115	Distinct Subsequences	Hard		hot
✅	116	Populating Next Right Pointers in Each Node	Medium
✅	117	Populating Next Right Pointers in Each Node II	Hard
✅	118	Pascal's Triangle	Medium
✅	120	Triangle	Medium
✅	121	Best Time to Buy and Sell Stock	Medium
✅	122	Best Time to Buy and Sell Stock II	Medium
✅	123	Best Time to Buy and Sell Stock III	Hard
✅	124	Binary Tree Maximum Path Sum	Hard		hot
✅	128	Longest Consecutive Sequence	Medium
✅	129	Sum Root to Leaf Numbers	Medium
✅	130	Surrounded Regions	Medium
✅	131	Palindrome Partitioning	Medium
✅	132	Palindrome Partitioning II	Hard
✅	133	Clone Graph	Medium
✅	135	Candy	Hard		hot
✅	136	Single Number	Medium
✅	137	Single Number II	Medium
✅	138	Copy List with Random Pointer	Hard
✅	139	Word Break	Medium
✅	141	Linked List Cycle	Medium
✅	142	Linked List Cycle II	Medium
✅	143	Reorder List	Medium
✅	144	Binary Tree Preorder Traversal	Easy
✅	145	Binary Tree Postorder Traversal	Easy
✅	146	LRU Cache	Medium		hot
✅	147	Insertion Sort List	Medium
✅	148	Sort List	Medium
✅	150	Evaluate Reverse Polish Notation	Medium
✅	152	Maximum Product Subarray	Medium
✅	153	Find Minimum in Rotated Sorted Array	Medium
✅	154	Find Minimum in Rotated Sorted Array II	Hard
✅	155	Min Stack	Easy
✅	160	Intersection of Two Linked Lists	Easy
⬜	162	Find Peak Element	Medium
✅	164	Maximum Gap	Hard
✅	169	Majority Element	Easy
✅	173	Binary Search Tree Iterator	Medium
✅	174	Dungeon Game	Hard
⬜	179	Largest Number	Medium
✅	188	Best Time to Buy and Sell Stock IV	Hard		hot
✅	189	Rotate Array	Medium
✅	190	Reverse Bits	Easy
✅	191	Number of 1 Bits	Easy
✅	198	House Robber	Easy
✅	199	Binary Tree Right Side View	Medium
✅	200	Number of Islands	Medium
✅	206	Reverse Linked List	Easy
✅	208	Implement Trie (Prefix Tree)	Medium
✅	209	Minimum Size Subarray Sum	Medium
✅	211	Add and Search Word - Data structure design	Medium
✅	212	Word Search II	Hard
✅	213	House Robber II	Medium
⬜	214	Shortest Palindrome	Hard
✅	215	Kth Largest Element in an Array	Medium
✅	216	Combination Sum III	Medium
✅	217	Contains Duplicate	Easy
✅	218	The Skyline Problem	Hard
✅	221	Maximal Square	Medium
✅	222	Count Complete Tree Nodes	Medium
✅	224	Basic Calculator	Medium		hot
✅	225	Implement Stack using Queues	Medium
✅	226	Invert Binary Tree	Easy
✅	232	Implement Queue using Stacks	Easy
⬜	233	Number of Digit One	Hard
✅	234	Palindrome Linked List	Easy
✅	235	Lowest Common Ancestor of a Binary Search Tree	Medium
✅	236	Lowest Common Ancestor of a Binary Tree	Medium
✅	237	Delete Node in a Linked List	Easy
✅	239	Sliding Window Maximum	Hard
✅	256	Paint House $	Medium
✅	257	Binary Tree Paths	Easy
✅	260	Single Number III	Medium
✅	264	Ugly Number II	Medium
✅	265	Paint House II $	Hard
✅	268	Missing Number	Easy
✅	278	First Bad Version	Easy
✅	279	Perfect Squares	Medium
✅	283	Move Zeroes	Easy
✅	285	Inorder Successor in BST $	Medium
✅	295	Find Median from Data Stream	Hard		hot
✅	297	Serialize and Deserialize Binary Tree	Medium
✅	300	Longest Increasing Subsequence	Medium
✅	303	Range Sum Query - Immutable	Easy
✅	304	Range Sum Query 2D - Immutable	Medium
✅	309	Best Time to Buy and Sell Stock with Cooldown	Medium
⬜	312	Burst Balloons	Hard
✅	316	Remove Duplicate Letters	Medium
✅	322	Coin Change	Medium
✅	329	Longest Increasing Path in a Matrix	Medium		hot
✅	337	House Robber III	Medium
✅	338	Counting Bits	Medium
✅	340	Longest Substring with At Most K Distinct Characters $	Hard
✅	343	Integer Break	Medium
✅	344	Reverse String	Easy
✅	347	Top K Frequent Elements	Medium
✅	349	Intersection of Two Arrays	Easy
✅	354	Russian Doll Envelopes	Hard
✅	363	Max Sum of Rectangle No Larger Than K	Hard
✅	368	Largest Divisible Subset	Medium
✅	370	Range Addition $	Medium
✅	377	Combination Sum IV	Medium
✅	394	Decode String	Medium
✅	401	Binary Watch	Easy
✅	402	Remove K Digits	Medium
✅	403	Frog Jump	Hard
✅	404	Sum of Left Leaves	Easy
⬜	407	Trapping Rain Water II	Hard
✅	410	Split Array Largest Sum	Hard		hot
✅	413	Arithmetic Slices	Medium
✅	416	Partition Equal Subset Sum	Medium
✅	426	Convert Binary Search Tree to Sorted Doubly Linked List	Medium
✅	437	Path Sum III	Easy
✅	438	Find All Anagrams in a String	Easy
✅	440	K-th Smallest in Lexicographical Order	Hard		hot
✅	448	Find All Numbers Disappeared in an Array	Easy
✅	449	Serialize and Deserialize BST	Medium
✅	450	Delete Node in a BST	Medium
✅	451	Sort Characters By Frequency	Medium
⬜	459	Repeated Substring Pattern	Easy
✅	460	LFU Cache	Hard		hot
✅	461	Hamming Distance	Easy
✅	474	Ones and Zeroes	Medium
✅	475	Heaters	Medium
⬜	488	Zuma Game	Hard
✅	494	Target Sum	Medium
✅	496	Next Greater Element I	Easy
✅	501	Find Mode in Binary Search Tree	Easy
✅	503	Next Greater Element II	Medium
✅	509	Fibonacci Number	Easy
✅	510	Inorder Successor in BST II $	Medium
✅	518	Coin Change 2	Medium
✅	529	Minesweeper	Medium
✅	538	Convert BST to Greater Tree	Medium
✅	542	01 Matrix	Medium
✅	543	Diameter of Binary Tree	Easy
✅	545	Boundary of Binary Tree	Medium
✅	560	Subarray Sum Equals K	Medium
✅	567	Permutation in String	Medium
✅	572	Subtree of Another Tree	Easy
✅	581	Shortest Unsorted Continuous Subarray	Medium
✅	583	Delete Operation for Two Strings	Medium
✅	617	Merge Two Binary Trees	Easy
✅	622	Design Circular Queue	Medium
✅	641	Design Circular Deque	Medium
⬜	647	24 Game	Hard
✅	650	2 Keys Keyboard	Medium
✅	652	Find Duplicate Subtrees	Medium
✅	671	Second Minimum Node In a Binary Tree	Easy
✅	673	Number of Longest Increasing Subsequence	Medium
✅	701	Insert into a Binary Search Tree	Medium
✅	703	Kth Largest Element in a Stream	Easy
✅	704	Binary Search	Easy
✅	705	Design HashSet	Easy
✅	706	Design HashMap	Easy
✅	707	Design Linked List	Easy
✅	712	Minimum ASCII Delete Sum for Two Strings	Medium
✅	714	Best Time to Buy and Sell Stock with Transaction Fee	Medium
✅	716	Max Stack $	Hard
✅	718	Maximum Length of Repeated Subarray	Medium
✅	733	Flood Fill	Easy
✅	739	Daily Temperatures	Medium
✅	740	Delete and Earn	Medium
✅	784	Letter Case Permutation	Easy
✅	801	Minimum Swaps To Make Sequences Increasing	Medium
✅	813	Largest Sum of Averages	Medium
✅	862	Shortest Subarray with Sum at Least K	Hard
✅	863	All Nodes Distance K in Binary Tree	Medium
✅	871	Minimum Number of Refueling Stops	Hard
✅	873	Length of Longest Fibonacci Subsequence	Medium
✅	879	Profitable Schemes	Hard
✅	889	Construct Binary Tree from Preorder and Postorder Traversal	Medium
✅	912	Sort an Array	Medium
✅	918	Maximum Sum Circular Subarray	Medium
✅	931	Minimum Falling Path Sum	Medium
✅	1008	Construct Binary Search Tree from Preorder Traversal	Medium
✅	1013	Partition Array Into Three Parts With Equal Sum	Easy
✅	1027	Longest Arithmetic Subsequence	Medium
✅	1028	Recover a Tree From Preorder Traversal	Hard
✅	1038	Binary Search Tree to Greater Sum Tree	Medium
⬜	1044	Longest Duplicate Substring	Hard
✅	1049	Last Stone Weight II	Medium
✅	1055	Shortest Way to Form String $	Medium
✅	1081	Smallest Subsequence of Distinct Characters	Medium
✅	1108	Defanging an IP Address	Easy
✅	1143	Longest Common Subsequence	Medium
✅	1155	Number of Dice Rolls With Target Sum	Medium
✅	1206	Design Skiplist	Hard
✅	1277	Count Square Submatrices with All Ones	Medium
✅	1372	Longest ZigZag Path in a Binary Tree	Medium
✅	1388	Pizza With 3n Slices	Hard
✅	1473	Paint House III	Hard
✅	1670	Design Front Middle Back Queue	Medium
✅	1804	Implement Trie II (Prefix Tree)	Medium
✅	1863	Sum of All Subset XOR Totals	Easy

标签序

数据结构

• Array
• String
• Matrix
• LinkedList
• Doubly-LinkedList
• HashTable
• Stack
• MonotonicStack
• Queue
• MonotonicQueue
• Heap(PriorityQueue)
• Tree
• BinaryTree
• BinarySearchTree
• Trie
• UnionFind

算法基础

• Sorting
• Recursion
• DivideandConquer
• BinarySearch
• Breadth-FirstSearch
• Depth-FirstSearch
• Backtracking
• Greedy
• TwoPointers
• SlidingWindow
• PrefixSum
• BitManipulation

动态规划

• DynamicProgramming

图论

• Graph

数学

• Math

设计

• Design