LeetCode 问题汇总（算法，难度，频率）


Id
Question
Difficulty
Frequency
Data Structures
Algorithms
1 Two Sum 2 5 array + set sort + two pointers
2 Add Two Numbers 3 4 linked list two pointers + math
3 Longest Substring Without Repeating Characters 3 2 string + hashtable two pointers
4 Median of Two Sorted Arrays 5 3 array binary search
5 Longest Palindromic Substring 4 2 string  
6 ZigZag Conversion 3 1 string  
7 Reverse Integer 2 3   math
8 String to Integer (atoi) 2 5 string math
9 Palindrome Number 2 2   math
10 Regular Expression Matching 5 3 string recursion + dp
11 Container With Most Water 3 2 array two pointers
12 Integer to Roman 3 4   math
13 Roman to Integer 2 4   math
14 Longest Common Prefix 2 1 string  
15 3Sum 3 5 array two pointers
16 3Sum Closest 3 1 array two pointers
17 Letter Combinations of a Phone Number 3 3 string dfs
18 4Sum 3 2 array  
19 Remove Nth Node From End of List 2 3 linked list two pointers
20 Valid Parentheses 2 5 string stack
21 Merge Two Sorted Lists 2 5 linked list sort + two pointers + merge
22 Generate Parentheses 3 4 string dfs
23 Merge k Sorted Lists 3 4 linked list + heap sort + two pointers + merge
24 Swap Nodes in Pairs 2 4 linked list  
25 Reverse Nodes in k-Group 4 2 linked list recursion + two pointers
26 Remove Duplicates from Sorted Array 1 3 array two pointers
27 Remove Element 1 4 array two pointers
28 Implement strStr() 4 5 string two pointers + KMP + rolling hash
29 Divide Two Integers 4 3   binary search + math
30 Substring with Concatenation of All Words 3 1 string two pointers
31 Next Permutation 5 2 array permutation
32 Longest Valid Parentheses 4 1 string dp
33 Search in Rotated Sorted Array 4 3 array binary search
34 Search for a Range 4 3 array binary search
35 Search Insert Position 2 2 array  
36 Valid Sudoku 2 2 array  
37 Sudoku Solver 4 2 array dfs
38 Count and Say 2 2 string two pointers
39 Combination Sum 3 3 array combination
40 Combination Sum II 4 2 array combination
41 First Missing Positive 5 2 array sort
42 Trapping Rain Water 4 2 array two pointers + stack
43 Multiply Strings 4 3 string two pointers + math
44 Wildcard Matching 5 3 string recursion + dp + greedy
45 Jump Game II 4 2 array  
46 Permutations 3 4 array permutation
47 Permutations II 4 2 array permutation
48 Rotate Image 4 2 array  
49 Anagrams 3 4 string + hashtable  
50 Pow(x, n) 3 5   binary search + math
51 N-Queens 4 3 array dfs
52 N-Queens II 4 3 array dfs
53 Maximum Subarray 3 3 array dp
54 Spiral Matrix 4 2 array  
55 Jump Game 3 2 array  
56 Merge Intervals 4 5 array + linked list + red-black tree sort + merge
57 Insert Interval 4 5 array + linked list + red-black tree sort + merge
58 Length of Last Word 1 1 string  
59 Spiral Matrix II 3 2 array  
60 Permutation Sequence 5 1   permutation + math
61 Rotate List 3 2 linked list two pointers
62 Unique Paths 2 3 array dp
63 Unique Paths II 3 3 array dp
64 Minimum Path Sum 3 3 array dp
65 Valid Number 2 5 string math
66 Plus One 1 2 array math
67 Add Binary 2 4 string two pointers + math
68 Text Justification 4 2 string  
69 Sqrt(x) 4 4   binary search
70 Climbing Stairs 2 5   dp
71 Simplify Path 3 1 string stack
72 Edit Distance 4 3 string dp
73 Set Matrix Zeroes 3 5 array  
74 Search a 2D Matrix 3 3 array binary search
75 Sort Colors 4 2 array sort + two pointers
76 Minimum Window Substring 4 2 string two pointers
77 Combinations 3 4   combination
78 Subsets 3 4 array recursion + combination
79 Word Search 3 4 array dfs
80 Remove Duplicates from Sorted Array II 2 2 array two pointers
81 Search in Rotated Sorted Array II 5 3 array binary search
82 Remove Duplicates from Sorted List II 3 3 linked list recursion + two pointers
83 Remove Duplicates from Sorted List 1 3 linked list  
84 Largest Rectangle in Histogram 5 2 array stack
85 Maximal Rectangle 5 1 array dp + stack
86 Partition List 3 3 linked list two pointers
87 Scramble String 5 2 string recursion + dp
88 Merge Sorted Array 2 5 array two pointers + merge
89 Gray Code 4 2   combination
90 Subsets II 4 2 array recursion + combination
91 Decode Ways 3 4 string recursion + dp
92 Reverse Linked List II 3 2 linked list two pointers
93 Restore IP Addresses 3 3 string dfs
94 Binary Tree Inorder Traversal 4 3 tree + hashtable recursion + morris + stack
95 Unique Binary Search Trees II 4 1 tree dp + dfs
96 Unique Binary Search Trees 3 1 tree dp
97 Interleaving String 5 2 string recursion + dp
98 Validate Binary Search Tree 3 5 tree dfs
99 Recover Binary Search Tree 4 2 tree dfs
100 Same Tree 1 1 tree dfs
101 Symmetric Tree 1 2 tree dfs
102 Binary Tree Level Order Traversal 3 4 tree bfs
103 Binary Tree Zigzag Level Order Traversal 4 3 queue + tree bfs + stack
104 Maximum Depth of Binary Tree 1 1 tree dfs
105 Construct Binary Tree from Preorder and Inorder Tr 3 3 array + tree dfs
106 Construct Binary Tree from Inorder and Postorder T 3 3 array + tree dfs
107 Binary Tree Level Order Traversal II 3 1 tree bfs
108 Convert Sorted Array to Binary Search Tree 2 3 tree dfs
109 Convert Sorted List to Binary Search Tree 4 3 linked list recursion + two pointers
110 Balanced Binary Tree 1 2 tree dfs
111 Minimum Depth of Binary Tree 1 1 tree dfs
112 Path Sum 1 3 tree dfs
113 Path Sum II 2 2 tree dfs
114 Flatten Binary Tree to Linked List 3 3 tree recursion + stack
115 Distinct Subsequences 4 2 string dp
116 Populating Next Right Pointers in Each Node 3 3 tree dfs
117 Populating Next Right Pointers in Each Node II 4 2 tree dfs
118 Pascal‘s Triangle 2 1 array  
119 Pascal‘s Triangle II 2 1 array  
120 Triangle 3 1 array dp
121 Best Time to Buy and Sell Stock 2 1 array dp
122 Best Time to Buy and Sell Stock II 3 1 array greedy
123 Best Time to Buy and Sell Stock III 4 1 array dp
124 Binary Tree Maximum Path Sum 4 2 tree dfs
125 Valid Palindrome 2 5 string two pointers
126 Word Ladder II 1 1    
127 Word Ladder 3 5 graph bfs + shortest path
128 Longest Consecutive Sequence 4 3 array  
129 Sum Root to Leaf Numbers 2 4 tree dfs
130 Surrounded Regions 4 3 array bfs + dfs
131 Palindrome Partitioning 3 4 string dfs
132 Palindrome Partitioning II 4 3 string dp
时间： 2024-08-04 03:41:57

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