algorithms-leetcode

TOP 100 https://leetcode.com/problem-list/top-100-liked-questions/

参考题解

• 分类刷，题解详细，多语言 https://github.com/youngyangyang04/leetcode-master#toc2
• 中文leetcode https://leetcode.cn/problemset/all/
• labuladong https://labuladong.gitee.io/algo/

其他

• https://siddontang.gitbooks.io/leetcode-solution/content/index.html
• python版: http://bookshadow.com/leetcode/

Leetcode problems classified by company:

• https://blogdesand.wordpress.com/
• https://github.com/duanehutchins/leetcode-questions-by-company

FT - Fast Try

目录

已完成题目

题号	名称	难度	标签	备注
1	Two Sum	Easy	Hash Table
2	Add Two Numbers	Medium	Linked List
3	Longest Substring Without Repeating Characters	Medium	Sliding Window,Hash Table
5	Longest Palindromic Substring	Medium	Dynamic Programming/Two Pointers	TODO 一题多解
6	Zigzag Conversion	Medium		一题多解TODO
10	Regular Expression Matching	Hard
11	Container With Most Water	Medium	Two Pointers
15	3Sum	Medium	Two Pointers
17	Letter Combinations of a Phone Number	Medium	Backtracking
19	Remove Nth Node From End of List	Medium	Two Pointers
20	Valid Parentheses	Easy	Stack
21	Merge Two Sorted Lists	Easy
22	Generate Parentheses	Medium	Dynamic Programming,Backtracking	复习1次
23	Merge k Sorted Lists	Hard
24	Swap Nodes in Pairs	Medium	Linked List/Recursion	一题多解决
26	Remove Duplicates from Sorted Array	Easy
27	Remove Element	Easy	Two Pointers	一题多解
31	Next Permutation	Medium
33	Search in Rotated Sorted Array	Medium	Binary Search	一题多解
34	Find First and Last Position of Element in Sorted Array	Medium	Binary Search
35	Search Insert Position	Easy	Binary Search
39	Combination Sum	Medium	Backtracking
41	First Missing Positive	Hard	Hash Table	一题多解
42	Trapping Rain Water	Hard	Dynamic Programming/Stack/Two Pointers	FT, TODO 一题多解，重点复习
45	Jump Game II	Medium	Dynamic Programming/Greedy	一题多解
46	Permutations	Medium	Backtracking
48	Rotate Image	Medium		TODO 一题多解
49	Group Anagrams	Medium		FT，TODO 一题多解
53	Maximum Subarray	Medium	Dynamic Programming/divide and conquer	一题多解
54	Spiral Matrix	Medium		FT
55	Jump Game	Medium	Greedy
56	Merge Intervals	Medium	Sort	FT
62	Unique Paths	Medium
63	Unique Paths II	Medium		待重做
64	Minimum Path Sum	Medium	Dynamic Programming	FT
70	Climbing Stairs	Easy	Dynamic Programming/Recursion	一题多解
72	Edit Distance	Hard	Dynamic Programming
73	Set Matrix Zeroes	Medium	Array	FT，TODO待优化
74	Search a 2D Matrix	Medium	Binary Search	FT, TODO 两次二分
75	Sort Colors	Medium	Two Pointers/	一题多解, TODO
77	Combinations	Medium	Backtracking
78	Subsets	Medium	Backtracking	FT
79	Word Search	Medium	Backtracking	待查题解
94	Binary Tree Inorder Traversal	Easy	Binary Tree/Stack	一题多解，待复习
96	Unique Binary Search Trees	Medium	Dynamic Programming
98	Validate Binary Search Tree	Medium	Binary Search/Recursion	一题多解
101	Symmetric Tree	Easy	Binary Tree/Queue/Stack	一题多解
102	Binary Tree Level Order Traversal	Medium	Binary Tree,DFS/BFS	一题多解
104	Maximum Depth of Binary Tree	Easy	Binary Tree/Queue
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Binary Tree,divide and conquer	只写了常规解法
106	Construct Binary Tree from Inorder and Postorder Traversal	Medium	Binary Tree,divide and conquer
107	Binary Tree Level Order Traversal II	Medium	Binary Tree,DFS/BFS	同第102题,TODO
110	Balanced Binary Tree	Easy	Binary Tree/Queue
111	Minimum Depth of Binary Tree	Easy	Binary Tree/Queue
112	Path Sum	Easy	Binary Tree/Queue
113	Path Sum II	Easy	Binary Tree	TODO
114	Flatten Binary Tree to Linked List	Medium	Binary Tree	FT, TODO 待优化
115	Distinct Subsequences	Hard	Dynamic Programming	TODO待复习
120	Triangle	Medium
121	Best Time to Buy and Sell Stock	Easy		待查最优解，以及一题多解
122	Best Time to Buy and Sell Stock II	Medium	Dynamic Programming/Greedy	一题多解
128	Longest Consecutive Sequence	Medium	Hash Table	TODO一题多解
131	Palindrome Partitioning	Medium	Backtracking, Dynamic Programming	FT, TODO 待复习, 关联题目LeetCode 5
138	Copy List with Random Pointer	Medium	Hash Table	FT，一题多解
139	Word Break	Medium	Dynamic Programming,完全背包
141	Linked List Cycle	Easy	Two Pointers
142	Linked List Cycle II	Medium	Two Pointers/Hash Table	FT
144	Binary Tree Preorder Traversal	Easy	Binary Tree/Stack	一题多解
148	Sort List	Medium
150	Evaluate Reverse Polish Notation	Medium	Stack
152	Maximum Product Subarray	Medium	Dynamic Programming	FT
153	Find Minimum in Rotated Sorted Array	Medium
155	Min Stack	Medium	Stack	FT
162	Find Peak Element	Medium
169	Majority Element	Easy
198	House Robber	Medium	Dynamic Programming
199	Binary Tree Right Side View	Medium	Binary Tree
202	Happy Number	Easy
206	Reverse Linked List	Easy	Linked List/Recursion	一题多解
209	Minimum Size Subarray Sum	Medium	Sliding Window/Binary Search	一题多解
216	Combination Sum III	Medium	Backtracking	一题多解
221	Maximal Square	Medium
222	Count Complete Tree Nodes	Medium	Binary Tree/Binary Search	TODO一题多解
226	Invert Binary Tree	Easy	Binary Tree
230	Kth Smallest Element in a BST	Medium	Binary Tree	只写了常规解法
231	Power of Two	Easy
236	Lowest Common Ancestor of a Binary Tree	Medium	Binary Tree
239	Sliding Window Maximum	Hard	Sliding Window,Monotonic Queue
257	Binary Tree Paths	Easy
268	Missing Number	Easy	Hash Table/Bit Manipulation	一题多解
300	Longest Increasing Subsequence	Medium	Dynamic Programming,Binary Search	经典题
322	Coin Change	Medium	Dynamic Programming,完全背包
343	Integer Break	Medium	Dynamic Programming	一题多解
344	Reverse String	Easy
347	Top K Frequent Elements	Medium	Heap/Bucket Sort	一题多解
349	Intersection of Two Arrays	Easy
354	Russian Doll Envelopes	Hard
376	Wiggle Subsequence	Medium	Greedy/Dynamic Programming	TODO 一题多解
392	Is Subsequence	Easy	Dynamic Programming/Two Pointers	一题多解
404	Sum of Left Leaves	Easy	Binary Tree
416	Partition Equal Subset Sum	Medium	Dynamic Programming,01背包
455	Assign Cookies	Easy	Greedy
474	Ones and Zeroes	Medium	Dynamic Programming,01背包	TODO 二维解法
494	Target Sum	Medium	Dynamic Programming	TODO 一般解
501	Find Mode in Binary Search Tree	Easy	Binary Tree
513	Find Bottom Left Tree Value	Medium	Binary Tree
516	Longest Palindromic Subsequence	Dynamic Programming
518	Coin Change 2	Medium	Dynamic Programming,完全背包
530	Minimum Absolute Difference in BST	Easy	Binary Tree
541	Reverse String II	Easy	Two Pointers	TODO
583	Delete Operation for Two Strings	Medium	Dynamic Programming	TODO 一题多解
617	Merge Two Binary Trees	Easy	Binary Tree
637	Average of Levels in Binary Tree	Easy	Binary Tree
647	Palindromic Substrings	Medium	Dynamic Programming/Two Pointers	一题多解
654	Maximum Binary Tree	Medium	Binary Tree
674	Longest Continuous Increasing Subsequence	Easy	Dynamic Programming	一题多解，对比第300题
700	Search in a Binary Search Tree	Easy	Binary Search
704	Binary Search	Easy
718	Maximum Length of Repeated Subarray	Medium	Dynamic Programming	TODO 滚动数组写法
977	Squares of a Sorted Array	Easy	Two Pointers	TODO
1035	Uncrossed Lines	Medium	Dynamic Programming	同第1143题
1143	Longest Common Subsequence	Medium	Dynamic Programming	待优化

链表相关

题号	名称	难度	标签	备注
206	Reverse Linked List	Easy

206，141，21，19，876 单链表反转 链表中环的检测 两个有序的链表合并 删除链表倒数第 n 个结点 求链表的中间结点

栈相关 20,155,232,844,224,682,496.

二叉树

94、105、106、889 中序遍历

DP相关

基础题

• 509 斐波那契额数列
• 70 爬楼梯
• 746 最小花费爬楼梯
• 62 不同路径
• 63 不同路径II
• 343 整数拆分
• 96 不同的二叉搜索树