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230 Kth Smallest Element in a BST 30.9% Medium
229 Majority Element II 22.1% Medium
228 Summary Ranges 19.6% Easy
227 Basic Calculator II 17.6% Medium
226 Invert Binary Tree 35.5% Easy
225 Implement Stack using Queues 30.0% Medium
224 Basic Calculator 15.9% Medium
223 Rectangle Area 25.5% Easy
222 Count Complete Tree Nodes 19.7% Medium
221 Maximal Square 20.1% Medium
220 Contains Duplicate III 15.4% Medium
219 Contains Duplicate II 25.6% Easy
218 The Skyline Problem 16.4% Hard
217 Contains Duplicate 35.8% Easy
216 Combination Sum III 27.9% Medium
215 Kth Largest Element in an Array 27.2% Medium
214 Shortest Palindrome 16.9% Hard
213 House Robber II 26.4% Medium
212 Word Search II 15.0% Hard
211 Add and Search Word - Data structure design 20.6% Medium
210 Course Schedule II 19.4% Medium
209 Minimum Size Subarray Sum 23.0% Medium
208 Implement Trie (Prefix Tree) 24.9% Medium
207 Course Schedule 21.8% Medium
206 Reverse Linked List 31.6% Easy
205 Isomorphic Strings 24.3% Easy
204 Count Primes 19.0% Easy
203 Remove Linked List Elements 25.8% Easy
202 Happy Number 31.3% Easy
201 Bitwise AND of Numbers Range 23.8% Medium
200 Number of Islands 22.0% Medium
199 Binary Tree Right Side View 27.2% Medium
198 House Robber 28.9% Easy
191 Number of 1 Bits 37.4% Easy
190 Reverse Bits 28.4% Easy
189 Rotate Array 17.9% Easy
188 Best Time to Buy and Sell Stock IV 17.5% Hard
187 Repeated DNA Sequences 19.6% Medium
186 Reverse Words in a String II 31.3% Medium
179 Largest Number 15.7% Medium
174 Dungeon Game 17.8% Hard
173 Binary Search Tree Iterator 29.4% Medium
172 Factorial Trailing Zeroes 28.5% Easy
171 Excel Sheet Column Number 36.6% Easy
170 Two Sum III - Data structure design 24.8% Easy
169 Majority Element 35.2% Easy
168 Excel Sheet Column Title 18.1% Easy
167 Two Sum II - Input array is sorted 43.3% Medium
166 Fraction to Recurring Decimal 12.7% Medium
165 Compare Version Numbers 15.2% Easy
164 Maximum Gap 24.4% Hard
163 Missing Ranges 24.0% Medium
162 Find Peak Element 31.5% Medium
161 One Edit Distance 24.0% Medium
160 Intersection of Two Linked Lists 28.8% Easy
159 Longest Substring with At Most Two Distinct Characters 30.2% Hard
158 Read N Characters Given Read4 II - Call multiple times 22.3% Hard
157 Read N Characters Given Read4 29.8% Easy
156 Binary Tree Upside Down 34.2% Medium
155 Min Stack 18.6% Easy
154 Find Minimum in Rotated Sorted Array II 31.9% Hard
153 Find Minimum in Rotated Sorted Array 33.3% Medium
152 Maximum Product Subarray 19.4% Medium
151 Reverse Words in a String 15.1% Medium
150 Evaluate Reverse Polish Notation 21.1% Medium
149 Max Points on a Line 12.6% Hard
148 Sort List 22.0% Medium
147 Insertion Sort List 26.5% Medium
146 LRU Cache 15.0% Hard
145 Binary Tree Postorder Traversal 32.4% Hard
144 Binary Tree Preorder Traversal 36.2% Medium
143 Reorder List 21.0% Medium
142 Linked List Cycle II 31.3% Medium
141 Linked List Cycle 36.3% Medium
140 Word Break II 17.7% Hard
139 Word Break 23.0% Medium
138 Copy List with Random Pointer 25.1% Hard
137 Single Number II 35.0% Medium
136 Single Number 45.1% Medium
135 Candy 20.5% Hard
134 Gas Station 25.7% Medium
133 Clone Graph 24.0% Medium
132 Palindrome Partitioning II 19.7% Hard
131 Palindrome Partitioning 26.8% Medium
130 Surrounded Regions 14.7% Medium
129 Sum Root to Leaf Numbers 30.3% Medium
128 Longest Consecutive Sequence 29.4% Hard
127 Word Ladder 19.3% Medium
126 Word Ladder II 12.9% Hard
125 Valid Palindrome 22.0% Easy
124 Binary Tree Maximum Path Sum 21.5% Hard
123 Best Time to Buy and Sell Stock III 23.9% Hard
122 Best Time to Buy and Sell Stock II 38.3% Medium
121 Best Time to Buy and Sell Stock 32.7% Medium
120 Triangle 27.3% Medium
119 Pascal's Triangle II 29.5% Easy
118 Pascal's Triangle 30.1% Easy
117 Populating Next Right Pointers in Each Node II 32.0% Hard
116 Populating Next Right Pointers in Each Node 36.1% Medium
115 Distinct Subsequences 26.3% Hard
114 Flatten Binary Tree to Linked List 28.8% Medium
113 Path Sum II 26.6% Medium
112 Path Sum 29.8% Easy
111 Minimum Depth of Binary Tree 29.1% Easy
110 Balanced Binary Tree 32.0% Easy
109 Convert Sorted List to Binary Search Tree 27.9% Medium
108 Convert Sorted Array to Binary Search Tree 34.0% Medium
107 Binary Tree Level Order Traversal II 30.9% Easy
106 Construct Binary Tree from Inorder and Postorder Traversal 26.8% Medium
105 Construct Binary Tree from Preorder and Inorder Traversal 26.3% Medium
104 Maximum Depth of Binary Tree 45.1% Easy
103 Binary Tree Zigzag Level Order Traversal 26.4% Medium
102 Binary Tree Level Order Traversal 29.3% Easy
101 Symmetric Tree 31.6% Easy
100 Same Tree 41.7% Easy
99 Recover Binary Search Tree 24.3% Hard
98 Validate Binary Search Tree 20.6% Medium
97 Interleaving String 20.7% Hard
96 Unique Binary Search Trees 35.9% Medium
95 Unique Binary Search Trees II 28.0% Medium
94 Binary Tree Inorder Traversal 36.2% Medium
93 Restore IP Addresses 21.0% Medium
92 Reverse Linked List II 26.1% Medium
91 Decode Ways 16.4% Medium
90 Subsets II 27.7% Medium
89 Gray Code 32.8% Medium
88 Merge Sorted Array 29.6% Easy
87 Scramble String 24.3% Hard
86 Partition List 27.5% Medium
85 Maximal Rectangle 22.1% Hard
84 Largest Rectangle in Histogram 22.6% Hard
83 Remove Duplicates from Sorted List 34.5% Easy
82 Remove Duplicates from Sorted List II 25.0% Medium
81 Search in Rotated Sorted Array II 31.4% Medium
80 Remove Duplicates from Sorted Array II 30.5% Medium
79 Word Search 20.3% Medium
78 Subsets 28.2% Medium
77 Combinations 30.9% Medium
76 Minimum Window Substring 18.9% Hard
75 Sort Colors 32.5% Medium
74 Search a 2D Matrix 31.6% Medium
73 Set Matrix Zeroes 31.4% Medium
72 Edit Distance 26.2% Hard
71 Simplify Path 20.0% Medium
70 Climbing Stairs 34.3% Easy
69 Sqrt(x) 23.1% Medium
68 Text Justification 14.6% Hard
67 Add Binary 24.7% Easy
66 Plus One 30.4% Easy
65 Valid Number 11.4% Hard
64 Minimum Path Sum 32.2% Medium
63 Unique Paths II 28.0% Medium
62 Unique Paths 32.8% Medium
61 Rotate List 21.7% Medium
60 Permutation Sequence 22.8% Medium
59 Spiral Matrix II 31.8% Medium
58 Length of Last Word 28.0% Easy
57 Insert Interval 21.4% Hard
56 Merge Intervals 22.4% Hard
55 Jump Game 27.0% Medium
54 Spiral Matrix 20.8% Medium
53 Maximum Subarray 34.5% Medium
52 N-Queens II 35.9% Hard
51 N-Queens 26.5% Hard
50 Pow(x, n) 26.7% Medium
49 Anagrams 24.3% Medium
48 Rotate Image 32.0% Medium
47 Permutations II 25.8% Hard
46 Permutations 31.9% Medium
45 Jump Game II 24.2% Hard
44 Wildcard Matching 15.0% Hard
43 Multiply Strings 21.0% Medium
42 Trapping Rain Water 30.0% Hard
41 First Missing Positive 22.9% Hard
40 Combination Sum II 25.2% Medium
39 Combination Sum 27.9% Medium
38 Count and Say 25.3% Easy
37 Sudoku Solver 21.8% Hard
36 Valid Sudoku 27.2% Easy
35 Search Insert Position 35.4% Medium
34 Search for a Range 27.5% Medium
33 Search in Rotated Sorted Array 28.8% Hard
32 Longest Valid Parentheses 20.9% Hard
31 Next Permutation 24.9% Medium
30 Substring with Concatenation of All Words 19.5% Hard
29 Divide Two Integers 15.0% Medium
28 Implement strStr() 22.2% Easy
27 Remove Element 32.1% Easy
26 Remove Duplicates from Sorted Array 31.3% Easy
25 Reverse Nodes in k-Group 25.5% Hard
24 Swap Nodes in Pairs 32.4% Medium
23 Merge k Sorted Lists 21.1% Hard
22 Generate Parentheses 32.6% Medium
21 Merge Two Sorted Lists 32.6% Easy
20 Valid Parentheses 26.5% Easy
19 Remove Nth Node From End of List 27.1% Easy
18 4Sum 21.7% Medium
17 Letter Combinations of a Phone Number 25.8% Medium
16 3Sum Closest 26.9% Medium
15 3Sum 16.9% Medium
14 Longest Common Prefix 25.5% Easy
13 Roman to Integer 34.0% Easy
12 Integer to Roman 33.8% Medium
11 Container With Most Water 31.9% Medium
10 Regular Expression Matching 20.7% Hard
9 Palindrome Number 28.3% Easy
8 String to Integer (atoi) 13.0% Easy
7 Reverse Integer 25.0% Easy
6 ZigZag Conversion 21.8% Easy
5 Longest Palindromic Substring 20.7% Medium
4 Median of Two Sorted Arrays 17.3% Hard
3 Longest Substring Without Repeating Characters 20.5% Medium
2 Add Two Numbers 21.0% Medium
1 Two Sum 17.7% Medium

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