说明
说明
此版本是 https://books.halfrost.com/leetcode ⽹⻚的离线版，由于⽹⻚版实时会更新，所以此 PDF
版难免会有⼀些排版或者错别字。如果读者遇到了，可以到⽹⻚版相应⻚⾯，点击⻚⾯ edit 按钮，提交
pr 进⾏更改。此 PDF 版本号是 V1.5.20。PDF 永久更新地址是 https://github.com/halfrost/LeetCode
-Go/releases/，以版本号区分不同版本。笔者还是强烈推荐看在线版，有任何错误都会⽴即更新。如果
觉得此书对刷题有⼀点点帮助，可以给此书点⼀个 star，⿎励⼀下笔者早点更新更多题解。
版本号说明，V1.5.20，1 是⼤版本号，5 代表当前题解中有⼏百题，⽬前是 520 题，所以第⼆个
版本号是 5，20 代表当前题解中有⼏⼗题，⽬前是 520 题，所以第三个版本号是 20 。
⽬录
说明
⽬录
第⼀章 序章
关于 LeetCode
什么是 Cookbook
为什么会写这个开源书
关于书的封⾯
关于作者
关于书中的代码
⽬标读者
编程语⾔
使⽤说明
互动与勘误
最后
第⼆章 算法专题
Array
Backtracking
Binary Indexed Tree
Binary Search
Bit Manipulation
Breadth First Search
Depth First Search
Dynamic Programming
Hash Table
Linked List
Math
Segment Tree
Sliding Window
Sort
Stack
String
Tree
Two Pointers
Union Find
第三章 ⼀些模板
线段树 Segment Tree
并查集 UnionFind
第四章 Leetcode 题解
1. Two Sum
2. Add Two Numbers
3. Longest Substring Without Repeating Characters
4. Median of Two Sorted Arrays
7. Reverse Integer
9. Palindrome Number
11. Container With Most Water
13. Roman to Integer
15. 3Sum
16. 3Sum Closest
17. Letter Combinations of a Phone Number
18. 4Sum
19. Remove Nth Node From End of List
20. Valid Parentheses
21. Merge Two Sorted Lists
22. Generate Parentheses
23. Merge k Sorted Lists
24. Swap Nodes in Pairs
25. Reverse Nodes in k-Group
26. Remove Duplicates from Sorted Array
27. Remove Element
28. Implement strStr()
29. Divide Two Integers
30. Substring with Concatenation of All Words
33. Search in Rotated Sorted Array
34. Find First and Last Position of Element in Sorted Array
35. Search Insert Position
36. Valid Sudoku
37. Sudoku Solver
39. Combination Sum
40. Combination Sum II
41. First Missing Positive
42. Trapping Rain Water
46. Permutations
47. Permutations II
48. Rotate Image
49. Group Anagrams
50. Pow(x, n)
51. N-Queens
52. N-Queens II
53. Maximum Subarray
54. Spiral Matrix
55. Jump Game
56. Merge Intervals
57. Insert Interval
59. Spiral Matrix II
60. Permutation Sequence
61. Rotate List
62. Unique Paths
63. Unique Paths II
64. Minimum Path Sum
66. Plus One
67. Add Binary
69. Sqrt(x)
70. Climbing Stairs
71. Simplify Path
74. Search a 2D Matrix
75. Sort Colors
76. Minimum Window Substring
77. Combinations
78. Subsets
79. Word Search
80. Remove Duplicates from Sorted Array II
81. Search in Rotated Sorted Array II
82. Remove Duplicates from Sorted List II
83. Remove Duplicates from Sorted List
84. Largest Rectangle in Histogram
86. Partition List
88. Merge Sorted Array
89. Gray Code
90. Subsets II
91. Decode Ways
92. Reverse Linked List II
93. Restore IP Addresses
94. Binary Tree Inorder Traversal
95. Unique Binary Search Trees II
96. Unique Binary Search Trees
98. Validate Binary Search Tree
99. Recover Binary Search Tree
100. Same Tree
101. Symmetric Tree
102. Binary Tree Level Order Traversal
103. Binary Tree Zigzag Level Order Traversal
104. Maximum Depth of Binary Tree
105. Construct Binary Tree from Preorder and Inorder Traversal
106. Construct Binary Tree from Inorder and Postorder Traversal
107. Binary Tree Level Order Traversal II
108. Convert Sorted Array to Binary Search Tree
109. Convert Sorted List to Binary Search Tree
110. Balanced Binary Tree
111. Minimum Depth of Binary Tree
112. Path Sum
113. Path Sum II
114. Flatten Binary Tree to Linked List
120. Triangle
121. Best Time to Buy and Sell Stock
122. Best Time to Buy and Sell Stock II
124. Binary Tree Maximum Path Sum
125. Valid Palindrome
126. Word Ladder II
127. Word Ladder
128. Longest Consecutive Sequence
129. Sum Root to Leaf Numbers
130. Surrounded Regions
131. Palindrome Partitioning
136. Single Number
137. Single Number II
141. Linked List Cycle
143. Reorder List
144. Binary Tree Preorder Traversal
145. Binary Tree Postorder Traversal
147. Insertion Sort List
148. Sort List
150. Evaluate Reverse Polish Notation
151. Reverse Words in a String
152. Maximum Product Subarray
153. Find Minimum in Rotated Sorted Array
154. Find Minimum in Rotated Sorted Array II
155. Min Stack
160. Intersection of Two Linked Lists
162. Find Peak Element
164. Maximum Gap
167. Two Sum II - Input array is sorted
168. Excel Sheet Column Title
169. Majority Element
171. Excel Sheet Column Number
172. Factorial Trailing Zeroes
173. Binary Search Tree Iterator
174. Dungeon Game
179. Largest Number
187. Repeated DNA Sequences
190. Reverse Bits
191. Number of 1 Bits
198. House Robber
199. Binary Tree Right Side View
200. Number of Islands
201. Bitwise AND of Numbers Range
202. Happy Number
203. Remove Linked List Elements
204. Count Primes
205. Isomorphic Strings
206. Reverse Linked List
207. Course Schedule
