1
Two Sum
99
Link
36.4%
Easy
2
Add Two Numbers
99
Link
28.2%
Medium
13
Roman to Integer
99
47.0%
Easy
4
Median of Two Sorted Arrays
98
Link
22.4%
Hard
237
Delete Node in a Linked List
96
Link
47.1%
Easy
20
Valid Parentheses
95
33.7%
Easy
21
Merge Two Sorted Lists
95
Link
39.5%
Easy
5
Longest Palindromic Substring
94
Link
25.2%
Medium
206
Reverse Linked List
94
Link
46.3%
Easy
146
LRU Cache
94
18.9%
Hard
191
Number of 1 Bits
93
Link
40.0%
Easy
53
Maximum Subarray
93
40.0%
Easy
151
Reverse Words in a String
92
15.7%
Medium
23
Merge k Sorted Lists
92
Link
27.8%
Hard
141
Linked List Cycle
92
Link
35.2%
Easy
258
Add Digits
92
51.5%
Easy
121
Best Time to Buy and Sell Stock
91
Link
42.2%
Easy
15
3Sum
90
21.8%
Medium
238
Product of Array Except Self
89
49.9%
Medium
171
Excel Sheet Column Number
88
47.9%
Easy
88
Merge Sorted Array
88
32.1%
Easy
138
Copy List with Random Pointer
87
26.0%
Medium
26
Remove Duplicates from Sorted Array
86
Link
35.6%
Easy
200
Number of Islands
85
Link
35.8%
Medium
56
Merge Intervals
85
Link
31.2%
Medium
48
Rotate Image
85
40.2%
Medium
153
Find Minimum in Rotated Sorted Array
85
40.4%
Medium
8
String to Integer (atoi)
85
13.9%
Medium
160
Intersection of Two Linked Lists
84
Link
30.8%
Easy
33
Search in Rotated Sorted Array
82
32.1%
Medium
419
Battleships in a Board
82
62.4%
Medium
28
Implement strStr()
82
28.7%
Easy
173
Binary Search Tree Iterator
81
42.7%
Medium
46
Permutations
80
45.6%
Medium
54
Spiral Matrix
80
Link
26.7%
Medium
235
Lowest Common Ancestor of a Binary Search Tree
79
39.5%
Easy
273
Integer to English Words
78
22.5%
Hard
268
Missing Number
77
Link
44.4%
Easy
387
First Unique Character in a String
77
47.2%
Easy
189
Rotate Array
77
Link
25.1%
Easy
79
Word Search
73
27.6%
Medium
73
Set Matrix Zeroes
73
36.3%
Medium
218
The Skyline Problem
73
28.4%
Hard
24
Swap Nodes in Pairs
73
38.8%
Medium
204
Count Primes
70
26.7%
Easy
236
Lowest Common Ancestor of a Binary Tree
70
30.0%
Medium
124
Binary Tree Maximum Path Sum
70
26.7%
Hard
101
Symmetric Tree
70
Link
39.7%
Easy
162
Find Peak Element
69
Link
38.2%
Medium
125
Valid Palindrome
68
26.7%
Easy
116
Populating Next Right Pointers in Each Node
68
36.9%
Medium
168
Excel Sheet Column Title
67
26.8%
Easy
232
Implement Queue using Stacks
67
Link
37.5%
Easy
297
Serialize and Deserialize Binary Tree
66
34.1%
Hard
215
Kth Largest Element in an Array
65
40.0%
Medium
165
Compare Version Numbers
65
20.5%
Medium
55
Jump Game
65
Link
29.6%
Medium
102
Binary Tree Level Order Traversal
64
41.3%
Medium
445
Add Two Numbers II
63
46.0%
Medium
75
Sort Colors
62
38.5%
Medium
91
Decode Ways
61
20.1%
Medium
208
Implement Trie (Prefix Tree)
61
Link
29.8%
Medium
654
Maximum Binary Tree
61
Link
70.0%
Medium
112
Path Sum
59
34.4%
Easy
114
Flatten Binary Tree to Linked List
58
35.9%
Medium
25
Reverse Nodes in k-Group
58
31.1%
Hard
71
Simplify Path
55
25.9%
Medium
94
Binary Tree Inorder Traversal
53
Link
48.1%
Medium
300
Longest Increasing Subsequence
52
Link
38.7%
Medium
106
Construct Binary Tree from Inorder and Postorder Traversal
49
32.7%
Medium
212
Word Search II
49
24.1%
Hard
98
Validate Binary Search Tree
49
23.8%
Medium
174
Dungeon Game
47
23.9%
Hard
47
Permutations II
47
34.0%
Medium
117
Populating Next Right Pointers in Each Node II
46
33.9%
Medium
103
Binary Tree Zigzag Level Order Traversal
44
35.8%
Medium
285
Inorder Successor in BST
43
36.3%
Medium
213
House Robber II
40
34.4%
Medium
348
Design Tic-Tac-Toe
40
45.9%
Medium
672
Bulb Switcher II
34
Link
48.4%
Medium
513
Find Bottom Left Tree Value
30
56.1%
Medium
186
Reverse Words in a String II
30
28.1%
Medium
270
Closest Binary Search Tree Value
29
40.2%
Easy
452
Minimum Number of Arrows to Burst Balloons
27
44.5%
Medium
650
2 Keys Keyboard
24
Link
44.9%
Medium
642
Design Search Autocomplete System
22
Link
31.0%
Hard
365
Water and Jug Problem
21
27.8%
Medium
567
Permutation in String
19
Link
36.6%
Medium
443
String Compression
18
Link
36.9%
Easy
333
Largest BST Subtree
8
30.7%
Medium
631
Design Excel Sum Formula
8
Link
27.3%
Hard
722
Remove Comments
6
Link
26.6%
Medium
651
4 Keys Keyboard
5
Link
49.1%
Medium
591
Tag Validator
2
Link
30.4%
Hard