867 |
Transpose Matrix |
Java |
Easy |
Array |
O(n) |
O(1) |
|
859 |
Buddy Strings |
Java |
Easy |
String |
O(n) |
|
|
858 |
Mirror Reflection |
Java |
Medium |
Math |
|
|
|
852 |
Peak Index in a Mountain Array |
Java |
Easy |
Binary Search |
|
|
|
848 |
Shifting Letters |
Java |
Medium |
String |
O(n) |
O(1) |
|
846 |
Hand of Straights |
Java Python |
Medium |
Map |
O(nlogn) |
|
|
844 |
Backspace String Compare |
Java |
Easy |
Two Pointers Stack |
|
|
|
832 |
Flipping an Image |
Java |
Easy |
Array |
O(n) |
O(n) |
|
819 |
Most Common Word |
Java |
Easy |
String |
O(n) |
|
γ |
812 |
Largest Triangle Area |
Java |
Easy |
Math |
O(n^3) |
|
links |
804 |
Unique Morse Code Words |
Java Scala |
Easy |
String |
O(n) |
O(n) |
≡ |
781 |
Rabbits in Forest |
Java |
Medium |
HashTable Math |
O(n) |
O(1) |
|
771 |
Jewels and Stones |
Java |
Easy |
HashTable |
O(n*m) |
|
|
763 |
Partition Labels |
Java |
Medium |
Two Pointer Greedy |
O(n) |
O(1) |
|
713 |
Subarray Product Less Than K |
Java |
Medium |
Array Two Poniter |
O(n) |
O(1) |
|
704 |
Binary Search |
Java |
Easy |
Binary Search |
O(logn) |
O(1) |
|
696 |
Robot Return to Origin |
Java |
Easy |
String |
O(n) |
O(1) |
links |
661 |
Image Smoother |
Java |
Easy |
Array |
O(n*m) |
O(1) |
|
657 |
Robot Return to Origin |
Java |
Easy |
String |
|
|
|
653 |
Two Sum IV - Input is a BST |
Java |
Easy |
Tree |
O(n) |
|
γ |
643 |
Maximum Average Subarray I |
Java |
Easy |
Array |
O(n) |
|
γ |
637 |
Average of Levels in Binary Tree |
Java |
Easy |
Tree BFS |
|
|
|
622 |
Design Circular Queue |
Java |
Medium |
Design Queue |
O(n) |
O(1) |
循环队列 |
599 |
Minimum Index Sum of Two Lists |
Java |
Easy |
Hash Table |
O(n) |
|
|
561 |
Array Partition I |
Java |
Easy |
Array |
|
|
|
477 |
Total Hamming Distance |
Java |
Medium |
Bit Manipulation |
O(n) |
O(1) |
links |
418 |
SentenceScreenFitting ♥ |
|
Easy |
|
|
|
Locked |
416 |
Partition Equal Subset Sum |
Java |
Medium |
|
|
|
|
415 |
Add Strings |
Java |
Easy |
Math |
O(n) |
|
|
414 |
Third Maximum Number |
Java |
Easy |
Array |
O(n) |
O(1) |
|
413 |
Arithmetic Slices |
Java |
Medium |
|
|
|
|
412 |
Fizz Buzz |
Java |
Easy |
|
|
|
|
410 |
Split Array Largest Sum |
Java |
Hard |
|
|
|
|
409 |
Longest Palindrome |
Java |
Easy |
|
|
|
|
406 |
Queue Reconstruction by Height |
Java |
Medium |
|
|
|
|
405 |
Convert a Number to Hexadecimal |
Java |
Easy |
|
|
|
|
404 |
Sum of Left Leaves |
Java |
Easy |
|
|
|
|
403 |
Frog Jump |
Java |
Hard |
|
|
|
|
402 |
Remove K Digits |
Java |
Medium |
|
|
|
|
401 |
Binary Watch |
Java |
Easy |
|
|
|
|
400 |
Nth Digit |
Java |
Easy |
|
|
|
|
399 |
Evaluate Division |
Java |
Medium |
|
|
|
|
398 |
Random Pick Index |
Java |
Medium |
|
|
|
|
397 |
Integer Replacement |
Java |
Medium |
|
|
|
|
396 |
Rotate Function |
Java |
Easy |
|
|
|
|
395 |
Longest Substring with At Least K Repeating Characters |
Java |
Medium |
|
|
|
|
394 |
Decode String |
Java |
Medium |
|
|
|
|
393 |
UTF-8 Validation |
Java |
Medium |
|
|
|
|
392 |
Is Subsequence |
Java |
Medium |
|
|
|
|
391 |
Perfect Rectangle |
Java |
Hard |
|
|
|
|
390 |
Elimination Game |
Java |
Medium |
|
|
|
|
389 |
Find the Difference |
Java |
Easy |
|
|
|
|
388 |
Longest Absolute File Path |
Java |
Medium |
|
|
|
|
387 |
First Unique Character in a String |
Java |
Easy |
Hash Table String |
O(n) |
O(1) |
|
386 |
Lexicographical Numbers |
Java |
Medium |
|
|
|
|
385 |
Mini Parser |
Java |
Medium |
|
|
|
|
384 |
Shuffle an Array |
Java |
Medium |
|
|
|
|
383 |
Ransom Note |
Java |
Easy |
|
|
|
|
382 |
Linked List Random Node |
Java |
Medium |
|
|
|
|
381 |
Insert Delete GetRandom O(1) - Duplicates allowed |
Java |
Hard |
|
|
|
|
380 |
Insert Delete GetRandom O(1) |
Java |
Hard |
|
|
|
|
377 |
Combination Sum IV |
Java |
Medium |
|
|
|
|
376 |
Wiggle Subsequence |
Java |
Medium |
|
|
|
|
371 |
Sum of Two Integers |
Java |
Easy |
|
|
|
|
367 |
Valid Perfect Square |
Java |
Easy |
|
|
|
|
350 |
Intersection of Two Arrays II |
Java |
Easy |
|
|
|
|
349 |
Intersection of Two Arrays |
Java |
Easy |
|
|
|
|
347 |
Top K Frequent Elements |
Java |
Medium |
|
|
|
|
345 |
Reverse Vowels of a String |
Java |
Easy |
|
|
|
|
344 |
Reverse String |
Java |
Easy |
|
|
|
|
343 |
Integer Break |
Java |
Medium |
|
|
|
|
342 |
Power of Four |
Java |
Easy |
|
|
|
|
341 |
Flatten Nested List Iterator |
Java |
Medium |
|
|
|
|
338 |
Counting Bits |
Java |
Medium |
|
|
|
|
337 |
House Robber III |
Java |
Medium |
|
|
|
|
336 |
Palindrome Pairs |
Java |
Hard |
|
|
|
|
334 |
Increasing Triplet Subsequence |
Java |
Medium |
|
|
|
|
332 |
Reconstruct Itinerary |
Java |
Medium |
|
|
|
|
331 |
Verify Preorder Serialization of a Binary Tree |
Java |
Medium |
|
|
|
|
330 |
Patching Array |
Java |
Medium |
|
|
|
|
329 |
Longest Increasing Path in a Matrix |
Java |
Medium |
|
|
|
|
328 |
Odd Even Linked List |
Java |
Easy |
|
|
|
|
327 |
Count of Range Sum |
Java |
Hard |
|
|
|
|
326 |
Power of Three |
Java |
Easy |
|
|
|
|
324 |
Wiggle Sort II |
Java |
Medium |
|
|
|
|
322 |
Coin Change |
Java |
Medium |
|
|
|
|
321 |
Create Maximum Number |
Java |
Hard |
|
|
|
|
319 |
Bulb Switcher |
Java |
Medium |
|
|
|
|
318 |
Maximum Product of Word Lengths |
Java |
Medium |
|
|
|
|
316 |
Remove Duplicate Letters |
Java |
Hard |
|
|
|
|
315 |
Count of Smaller Numbers After Self |
Java |
Hard |
|
|
|
|
313 |
Super Ugly Number |
Java |
Medium |
|
|
|
|
312 |
Burst Balloons |
Java |
Hard |
|
|
|
|
310 |
Minimum Height Trees |
Java |
Medium |
|
|
|
|
307 |
Range Sum Query - Mutable |
Java |
Medium |
|
|
|
|
306 |
Additive Number |
Java |
Medium |
|
|
|
|
304 |
Range Sum Query 2D - Immutable |
Java |
Medium |
|
|
|
|
303 |
Range Sum Query - Immutable |
Java |
Easy |
|
|
|
|
301 |
Remove Invalid Parentheses |
Java |
Hard |
|
|
|
|
300 |
Longest Increasing Subsequence |
Java |
Medium |
|
|
|
|
299 |
Bulls and Cows |
Java |
Easy |
|
|
|
|
297 |
Serialize and Deserialize Binary Tree |
Java |
Medium |
|
|
|
|
295 |
Find Median from Data Stream |
Java |
Hard |
|
|
|
|
292 |
Nim Game |
Java |
Easy |
|
|
|
|
290 |
Word Pattern |
Java |
Easy |
|
|
|
|
287 |
Find the Duplicate Number |
Java |
Hard |
|
|
|
|
285 |
Inorder Successor in BST ♥ |
|
Medium |
|
|
|
locked |
284 |
Peeking Iterator |
Java |
Medium |
|
|
|
|
283 |
Move Zeroes |
Java |
Easy |
|
|
|
|
282 |
Expression Add Operators |
Java |
Hard |
|
|
|
|
279 |
Perfect Squares |
Java |
Medium |
|
|
|
|
278 |
First Bad Version |
Java |
Easy |
Binary Search |
O(logn) |
O(1) |
γ |
275 |
H-Index II |
Java |
Medium |
|
|
|
|
274 |
H-Index |
Java |
Medium |
|
|
|
|
273 |
Integer to English Words |
Java |
Medium |
|
|
|
|
268 |
Missing Number |
Java |
Medium |
|
|
|
|
264 |
Ugly Number II |
Java |
Medium |
|
|
|
|
263 |
Ugly Number |
Java |
Easy |
|
|
|
|
260 |
Single Number III |
Java |
Medium |
|
|
|
|
258 |
Add Digits |
Java |
Easy |
|
|
|
|
257 |
Binary Tree Paths |
Java |
Easy |
|
|
|
|
242 |
Valid Anagram |
Java |
Easy |
|
|
|
|
241 |
Different Ways to Add Parentheses |
Java |
Medium |
|
|
|
|
240 |
Search a 2D Matrix II |
Java |
Medium |
|
|
|
|
239 |
Sliding Window Maximum |
Java |
Hard |
|
|
|
|
238 |
Product of Array Except Self |
Java |
Medium |
|
|
|
|
237 |
Delete Node in a Linked List |
Java |
Easy |
|
|
|
|
236 |
Lowest Common Ancestor of a Binary Tree |
Java, Scala |
Medium |
|
|
|
|
235 |
Lowest Common Ancestor of a Binary Search Tree |
Java |
Easy |
|
|
|
|
234 |
Palindrome Linked List |
Java |
Easy |
|
|
|
|
233 |
Number of Digit One |
Java |
Medium |
|
|
|
|
232 |
Implement Queue using Stacks |
Java |
Easy |
Stack Design |
O(1) |
O(1) |
|
231 |
Power of Two |
Java |
Easy |
|
|
|
|
230 |
Kth Smallest Element in a BST |
Java |
Medium |
|
|
|
|
229 |
Majority Element II |
Java |
Medium |
|
|
|
|
228 |
Summary Ranges |
Java |
Easy |
|
|
|
|
227 |
Basic Calculator II |
Java |
Medium |
|
|
|
|
226 |
Invert Binary Tree |
Java |
Easy |
|
|
|
|
225 |
Implement Stack using Queues |
Java |
Medium |
|
|
|
|
224 |
Basic Calculator |
Java |
Medium |
|
|
|
|
223 |
Rectangle Area |
Java |
Easy |
|
|
|
|
222 |
Count Complete Tree Nodes |
Java |
Medium |
|
|
|
|
221 |
Maximal Square |
Java |
Medium |
|
|
|
|
220 |
Contains Duplicate III |
Java |
Medium |
|
|
|
|
219 |
Contains Duplicate II |
Java |
Easy |
|
|
|
|
218 |
The Skyline Problem |
Java |
Hard |
|
|
|
|
217 |
Contains Duplicate |
Java |
Easy |
|
|
|
|
216 |
Combination Sum III |
Java |
Medium |
|
|
|
|
215 |
Kth Largest Element in an Array |
Java |
Medium |
|
|
|
|
214 |
Shortest Palindrome |
Java |
Hard |
|
|
|
|
213 |
House Robber II |
Java |
Medium |
|
|
|
|
212 |
Word Search II |
Java |
Hard |
|
|
|
|
211 |
Add and Search Word - Data structure design |
Java |
Medium |
|
|
|
|
210 |
Course Schedule II |
Java |
Medium |
|
|
|
|
209 |
Minimum Size Subarray Sum |
Java |
Medium |
|
|
|
|
208 |
Implement Trie (Prefix Tree) |
Java |
Medium |
|
|
|
|
207 |
Course Schedule |
Java |
Medium |
|
|
|
|
206 |
Reverse Linked List |
Java, Java |
Easy |
|
|
|
|
205 |
Isomorphic Strings |
Java |
Easy |
|
|
|
|
204 |
Count Primes |
Java |
Easy |
|
|
|
|
203 |
Remove Linked List Elements |
Java |
Easy |
|
|
|
|
202 |
Happy Number |
Java |
Easy |
|
|
|
|
201 |
Bitwise AND of Numbers Range |
Java |
Medium |
|
|
|
|
200 |
Number of Islands |
Java |
Medium |
|
|
|
|
199 |
Binary Tree Right Side View |
Java |
Medium |
O(nlogn) |
|
Tree DFS BFS |
|
198 |
House Robber |
Java |
Easy |
|
|
|
|
195 |
|
|
|
|
|
|
shell |
194 |
|
|
|
|
|
|
shell |
193 |
|
|
|
|
|
|
shell |
192 |
|
|
|
|
|
|
shell |
191 |
Number of 1 Bits |
Java |
Easy |
|
|
|
|
190 |
Reverse Bits |
Java |
Easy |
|
|
|
|
189 |
Rotate Array |
Java, Scala |
Easy |
|
|
|
|
188 |
Best Time to Buy and Sell Stock IV |
Java |
Hard |
|
|
|
|
187 |
Repeated DNA Sequences |
Java |
Medium |
|
|
|
|
186 |
Reverse Words in a String II ♥ |
|
Medium |
|
|
|
locked |
179 |
Largest Number |
Java |
Medium |
|
|
|
|
174 |
Dungeon Game |
Java |
Hard |
|
|
|
|
173 |
Binary Search Tree Iterator |
Java, Scala |
Medium |
|
|
|
|
172 |
Factorial Trailing Zeroes |
Java |
Easy |
|
|
|
|
171 |
Excel Sheet Column Number |
Java |
Easy |
|
|
|
|
170 |
Two Sum III - Data structure design ♥ |
Java |
Easy |
|
|
|
|
169 |
Majority Element |
Java |
Easy |
|
|
|
|
168 |
Excel Sheet Column Title |
Java |
Easy |
|
|
|
|
167 |
Two Sum II - Input array is sorted ♥ |
Java |
Easy |
Two Pointer Array Binary Search |
O(n) |
O(1) |
|
166 |
Fraction to Recurring Decimal |
Java |
Medium |
|
|
|
|
165 |
Compare Version Numbers |
Java |
Easy |
|
|
|
|
164 |
Maximum Gap |
Java |
Hard |
|
|
|
|
163 |
Missing Ranges ♥ |
Java |
Medium |
|
|
|
|
162 |
Find Peak Element |
Java |
Medium |
|
|
|
|
161 |
One Edit Distance♥ |
Java |
Medium |
|
|
|
|
160 |
Intersection of Two Linked Lists |
Java |
Easy |
|
|
|
|
159 |
Longest Substring with At Most Two Distinct Characters ♥ |
Java |
Hard |
|
|
|
|
158 |
Read N Characters Given Read4 II - Call multiple times ♥ |
Java |
Hard |
|
|
|
|
157 |
Read N Characters Given Read4 ♥ |
Java |
Easy |
|
|
|
|
156 |
Binary Tree Upside Down ♥ |
Java |
Medium |
|
|
|
|
155 |
Min Stack |
Java, Scala |
Easy |
|
|
|
|
154 |
Find Minimum in Rotated Sorted Array II |
Java |
Hard |
|
|
|
|
153 |
Find Minimum in Rotated Sorted Array |
Java, Java |
Medium |
|
|
|
|
152 |
Maximum Product Subarray |
Java |
Medium |
|
|
|
|
151 |
Reverse Words in a String |
Java, Java |
Medium |
|
|
|
|
150 |
Evaluate Reverse Polish Notation |
Java |
Medium |
|
|
|
|
149 |
Max Points on a Line |
Java |
Hard |
|
|
|
|
148 |
Sort List |
Java |
Medium |
|
|
|
|
147 |
Insertion Sort List |
Java |
Medium |
|
|
|
|
146 |
LRU Cache |
Java, Scala |
Hard |
|
|
|
|
145 |
Binary Tree Postorder Traversal |
Java |
Hard |
|
|
|
|
144 |
Binary Tree Preorder Traversal |
Java, Java |
Medium |
|
|
|
|
143 |
Reorder List |
Java |
Medium |
|
|
|
|
142 |
Linked List Cycle II |
Java |
Medium |
|
|
|
|
141 |
Linked List Cycle |
Java |
Medium |
|
|
|
|
140 |
Word Break II |
Java |
Hard |
|
|
|
|
139 |
Word Break |
Java |
Medium |
|
|
|
|
138 |
Copy List with Random Pointer |
Java |
Hard |
|
|
|
|
137 |
Single Number II |
Java |
Medium |
|
|
|
|
136 |
Single Number |
Java |
Medium |
|
|
|
|
135 |
Candy |
Java |
Hard |
|
|
|
|
134 |
Gas Station |
Java |
Medium |
|
|
|
|
133 |
Clone Graph |
Java |
Medium |
|
|
|
|
132 |
Palindrome Partitioning II |
Java |
Hard |
|
|
|
|
131 |
Palindrome Partitioning |
Java |
Medium |
|
|
|
|
130 |
Surrounded Regions |
Java |
Medium |
|
|
|
|
129 |
Sum Root to Leaf Numbers |
Java |
Medium |
|
|
|
|
128 |
Longest Consecutive Sequence |
Java |
Hard |
|
|
|
|
127 |
Word Ladder |
Java |
Medium |
|
|
|
|
126 |
Word Ladder II |
Java |
Hard |
|
|
|
|
125 |
Valid Palindrome |
Java, Scala |
Easy |
|
|
|
|
124 |
Binary Tree Maximum Path Sum |
Java, Scala |
Hard |
|
|
|
|
123 |
Best Time to Buy and Sell Stock III |
Java |
Hard |
|
|
|
|
122 |
Best Time to Buy and Sell Stock II |
Java |
Medium |
|
|
|
|
121 |
Best Time to Buy and Sell Stock |
Java |
Medium |
|
|
|
|
120 |
Triangle |
Java, Java |
Medium |
|
|
|
|
119 |
Pascal’s Triangle II |
Java |
Easy |
|
|
|
|
118 |
Pascal’s Triangle |
Java |
Easy |
|
|
|
|
117 |
Populating Next Right Pointers in Each Node II |
Java |
Hard |
|
|
|
|
116 |
Populating Next Right Pointers in Each Node |
Java |
Medium |
|
|
|
|
115 |
Distinct Subsequences |
Java |
Hard |
|
|
|
|
114 |
Flatten Binary Tree to Linked List |
Java |
Medium |
|
|
|
|
113 |
Path Sum II |
Java |
Medium |
|
|
|
|
112 |
Path Sum |
Java |
Easy |
|
|
|
|
111 |
Minimum Depth of Binary Tree |
Java |
Easy |
|
|
|
|
110 |
Balanced Binary Tree |
Java, Java |
Easy |
|
|
|
|
109 |
Convert Sorted List to Binary Search Tree |
Java |
Medium |
|
|
|
|
108 |
Convert Sorted Array to Binary Search Tree |
Java |
Medium |
|
|
|
|
107 |
Binary Tree Level Order Traversal II |
Java |
Easy |
|
|
|
|
106 |
Construct Binary Tree from Inorder and Postorder Traversal |
Java |
Medium |
|
|
|
|
105 |
Construct Binary Tree from Preorder and Inorder Traversal |
Java |
Medium |
|
|
|
|
104 |
Maximum Depth of Binary Tree |
Java, Scala |
Easy |
|
|
|
|
103 |
Binary Tree Zigzag Level Order Traversal |
Java |
Medium |
|
|
|
|
102 |
Binary Tree Level Order Traversal |
Java, Scala |
Easy |
|
|
|
|
101 |
Symmetric Tree |
Java |
Easy |
Tree Breadth-first Search Depth-first Search |
O(nlogn) |
|
|
100 |
Same Tree |
Java |
Easy |
Tree Depth-first Search |
O(nlogn) |
|
|
99 |
Recover Binary Search Tree |
Java |
Hard |
|
|
|
|
98 |
Validate Binary Search Tree |
Java, Scala |
Medium |
|
|
|
|
97 |
Interleaving String |
Java |
Hard |
|
|
|
|
96 |
Unique Binary Search Trees |
Java |
Medium |
|
|
|
|
95 |
Unique Binary Search Trees II |
Java |
Medium |
|
|
|
|
94 |
Binary Tree Inorder Traversal |
Java |
Medium |
|
|
|
|
93 |
Restore IP Addresses |
Java |
Medium |
|
|
|
|
92 |
Reverse Linked List II |
Java, Scala |
Medium |
|
|
|
|
91 |
Decode Ways |
Java |
Medium |
|
|
|
|
90 |
Subsets II |
Java |
Medium |
|
|
|
|
89 |
Gray Code |
Java |
Medium |
|
|
|
|
88 |
Merge Sorted Array |
Java |
Easy |
|
|
|
|
87 |
Scramble String |
Java |
Hard |
|
|
|
|
86 |
Partition List |
Java |
Medium |
|
|
|
|
85 |
Maximal Rectangle |
Java |
Hard |
|
|
|
|
84 |
Largest Rectangle in Histogram |
Java |
Hard |
|
|
|
|
83 |
Remove Duplicates from Sorted List |
Java |
Easy |
|
|
|
|
82 |
Remove Duplicates from Sorted List II |
Java |
Medium |
|
|
|
|
81 |
Search in Rotated Sorted Array II |
Java |
Medium |
|
|
|
|
80 |
Remove Duplicates from Sorted Array II |
Java |
Medium |
|
|
|
|
79 |
Word Search |
Java |
Medium |
|
|
|
|
78 |
Subsets |
Java, Scala |
Medium |
|
|
|
|
77 |
Combinations |
Java |
Medium |
|
|
|
|
76 |
Minimum Window Substring |
Java |
Hard |
|
|
|
|
75 |
Sort Colors |
Java |
Medium |
|
|
|
|
74 |
Search a 2D Matrix |
Java, Scala |
Medium |
|
|
|
|
73 |
Set Matrix Zeroes |
Java |
Medium |
|
|
|
|
72 |
Edit Distance |
Java |
Hard |
|
|
|
|
71 |
Simplify Path |
Java |
Medium |
|
|
|
|
70 |
Climbing Stairs |
Java |
Easy |
|
|
|
|
69 |
Sqrt(x) |
Java |
Medium |
|
|
|
|
68 |
Text Justification |
Java |
Hard |
|
|
|
|
67 |
Add Binary |
Java |
Easy |
|
|
|
|
66 |
Plus One |
Java |
Easy |
Array Math |
O(n) |
O(1) |
|
65 |
Valid Number |
Java |
Easy |
|
|
|
|
64 |
Minimum Path Sum |
Java |
Medium |
Array Dynamic Programming |
O(M*N) |
O(1) |
|
63 |
Unique Paths II |
Java |
Medium |
Array Dynamic Programming |
O(w*h) |
O(1) |
|
62 |
Unique Paths |
Java, Scala |
Medium |
|
|
|
|
61 |
Rotate List |
Java |
Medium |
|
|
|
|
60 |
Permutation Sequence |
Java |
Medium |
|
|
|
|
59 |
Spiral Matrix II |
Java |
Medium |
Array |
O(n^2) |
O(1) |
|
58 |
Length of Last Word |
Java |
Easy |
|
|
|
|
57 |
Insert Interval |
Java |
Hard |
|
|
|
|
56 |
Merge Intervals |
Java |
Hard |
|
|
|
|
55 |
Jump Game |
Java |
Medium |
Array Greedy |
O(n) |
O(1) |
Q45 |
54 |
Spiral Matrix |
Java |
Medium |
|
|
|
|
53 |
Maximum Subarray |
Java |
Medium |
Array Dynamic Programming Divide and Conquer |
O(n) |
|
|
52 |
N-Queens II |
Java |
Hard |
|
|
|
|
51 |
N-Queens |
Java |
Hard |
|
|
|
|
50 |
“Pow(x, n)” |
Java |
Medium |
|
|
|
|
49 |
Group Anagrams |
Java |
Medium |
|
|
|
|
48 |
Rotate Image |
Java |
Medium |
|
|
|
|
47 |
Permutations II |
Java |
Hard |
|
|
|
|
46 |
Permutations |
Java |
Medium |
|
|
|
|
45 |
Jump Game II |
Java |
Hard |
Array Greedy |
O(n) |
O(1) |
Q55 |
44 |
Wildcard Matching |
Java |
Hard |
|
|
|
|
43 |
Multiply Strings |
Java |
Medium |
|
|
|
|
42 |
Trapping Rain Water |
Java |
Hard |
|
|
|
|
41 |
First Missing Positive |
Java |
Hard |
Array |
O(n) |
O(1) |
分桶 |
40 |
Combination Sum II |
Java |
Medium |
|
|
|
|
39 |
Combination Sum |
Java |
Medium |
|
|
|
|
38 |
Count and Say |
Java |
Easy |
|
|
|
|
37 |
Sudoku Solver |
Java |
Hard |
|
|
|
|
36 |
Valid Sudoku |
Java |
Easy |
|
|
|
|
35 |
Search Insert Position |
Java |
Easy |
Array Binary Search |
O(N) |
|
|
34 |
Find First and Last Position of Element in Sorted Array |
Java |
Medium |
Array Binary Search |
O(n) |
O(1) |
|
33 |
Search in Rotated Sorted Array |
Java |
Medium |
Array Binary Search |
O(logn) |
O(1) |
二分查找法 |
32 |
Longest Valid Parentheses |
Java |
Hard |
String Dynamic Programming |
|
|
|
31 |
Next Permutation |
Java |
Medium |
|
|
|
|
30 |
Substring with Concatenation of All Words |
Java |
Hard |
String Hash Table Two Pointer |
O(M*N) |
|
|
29 |
Divide Two Integers |
Java |
Medium |
|
|
|
|
28 |
Implement strStr() |
Java, Scala |
Easy |
|
|
|
|
27 |
Remove Element |
Java |
Easy |
|
|
|
|
26 |
Remove Duplicates from Sorted Array |
Java |
Easy |
Array Two Pointer |
O(n) |
O(1) |
|
25 |
Reverse Nodes in k-Group |
Java |
Hard |
|
|
|
|
24 |
Swap Nodes in Pairs |
Java |
Medium |
|
|
|
|
23 |
Merge k Sorted Lists |
Java |
Hard |
|
|
|
|
22 |
Generate Parentheses |
Java |
Medium |
|
|
|
|
21 |
Merge Two Sorted Lists |
Java |
Easy |
|
|
|
|
20 |
Valid Parentheses |
Java |
Easy |
String Stack |
O(n) |
|
|
19 |
Remove Nth Node From End of List |
Java |
Medium |
Linked List Two Pointer |
O(N) |
|
γ |
18 |
4Sum |
Java |
Medium |
Array HashTable TwoPointer |
O(N^4) |
|
Q15 |
17 |
Letter Combinations of a Phone Number |
Java |
Medium |
String BackTracking |
O(n^3) |
|
queue |
16 |
3Sum Closest |
Java |
Medium |
Array Two Point |
O(n^2) |
|
Q15 |
15 |
3Sum |
Java |
Medium |
Array Two Point |
O(n^2) |
|
good γ |
14 |
Longest Common Prefix |
Java |
Easy |
String |
O(M*N) |
|
|
13 |
Roman to Integer |
Java |
Easy |
Math String |
|
|
Q12 |
12 |
Integer to Roman |
Java |
Medium |
Math String |
|
|
Q13 |
11 |
Container With Most Water |
Java |
Medium |
|
|
|
|
10 |
Regular Expression Matching |
Java |
Hard |
String Dynamic Programming Backtracking |
|
|
|
9 |
Palindrome Number |
Java |
Easy |
Math |
O(n) |
O(1) |
回文 |
8 |
String to Integer (atoi) |
Java |
Medium |
Math String |
|
|
|
7 |
Reverse Integer |
Java Scala |
Easy |
Math |
|
|
|
6 |
ZigZag Conversion |
Java |
Medium |
String |
|
|
|
5 |
Longest Palindromic Substring |
Java |
Medium |
String Dynamic Programming |
|
|
|
4 |
Median of Two Sorted Arrays |
Java |
Hard |
|
|
|
|
3 |
Longest Substring Without Repeating Characters |
Java |
Medium |
|
|
|
|
2 |
Add Two Numbers |
Java |
Medium |
|
|
|
|
1 |
Two Sum |
Python Java Scala |
Easy |
Array HashTable |
|
|
|