| 1 |
Two Sum |
Java |
Easy |
| 2 |
Add Two Numbers |
Java |
Medium |
| 3 |
Longest Substring Without Repeating Characters |
Java |
Medium |
| 5 |
Longest Palindromic Substring |
Java |
Medium |
| 9 |
Palindrome Number |
Java |
Easy |
| 11 |
Container With Most Water |
Java |
Medium |
| 13 |
Roman To Integer |
Java |
Easy |
| 14 |
Longest Common Prefix |
Java |
Easy |
| 16 |
3 Sum Closest |
Java |
Easy |
| 17 |
Letter Combinations of a Phone Number |
Java |
Medium |
| 19 |
Remove Nth Node From End of List |
Java |
Medium |
| 20 |
valid parentheses |
Java |
Easy |
| 21 |
Merge Two Sorted Lists |
Java |
Easy |
| 22 |
Generate Parentheses |
Java |
Medium |
| 26 |
Remove Duplicates from Sorted Array |
Java |
Easy |
| 27 |
Remove Element |
Java |
Easy |
| 28 |
Implement Str |
Java |
Easy |
| 33 |
Search in Rotated Sorted Array |
Java |
Medium |
| 34 |
Find First and Last Position of Element in Sorted Array |
Java |
Medium |
| 35 |
Search Insert Position |
Java |
Easy |
| 38 |
Count and Say |
Java |
Easy |
| 39 |
Combination Sum |
Java |
Medium |
| 40 |
Combination Sum II |
Java |
Medium |
| 45 |
Jump Game II |
Java |
Medium |
| 46 |
Permutations |
Java |
Medium |
| 47 |
Permutations II |
Java |
Medium |
| 53 |
Maximum Subarray |
Java |
Easy |
| 54 |
Spiral Matrix |
Java |
Medium |
| 55 |
Jump Game |
Java |
Medium |
| 58 |
Length of Last Word |
Java |
Easy |
| 61 |
Rotate List |
Java |
Medium |
| 62 |
Unique Paths |
Java |
Medium |
| 66 |
Plus One |
Java |
Easy |
| 67 |
Add Binary |
Java |
Easy |
| 69 |
Sqrt(x) |
Java |
Easy |
| 70 |
Climbing Stairs |
Java |
Easy |
| 73 |
Set Matrix Zeroes |
Java |
Medium |
| 74 |
Search a 2D Matrix |
Java |
Medium |
| 75 |
Sort Colors |
Java |
Easy |
| 76 |
Minimum Window Substring |
Java |
Hard |
| 77 |
Combinations |
Java |
Medium |
| 78 |
Subsets |
Java |
Medium |
| 79 |
Word Search |
Java |
Medium |
| 80 |
Remove Duplicates from Sorted Array II |
Java |
Medium |
| 81 |
Search in Rotated Sorted Array II |
Java |
Medium |
| 82 |
Remove Duplicates from Sorted List II |
Java |
Medium |
| 83 |
Remove Duplicates from Sorted List |
Java |
Easy |
| 88 |
Merge Sorted Array |
Java |
Easy |
| 90 |
Subsets II |
Java |
Medium |
| 92 |
Reverse Linked List II |
Java |
Medium |
| 100 |
Same Tree |
Java |
Easy |
| 101 |
Symmetric Tree |
Java |
Easy |
| 104 |
Maximum Depth of Binary Tree |
Java |
Easy |
| 107 |
Binary Tree Level Order Traversal II |
Java |
Easy |
| 108 |
Convert Sorted Array to Binary Search Tree |
Java |
Easy |
| 110 |
Balanced Binary Tree |
Java |
Easy |
| 111 |
Minimum Depth of Binary Tree |
Java |
Easy |
| 112 |
Path Sum |
Java |
Easy |
| 115 |
Distinct Subsequences |
Java |
Hard |
| 116 |
Populating Next Right Pointers in Each Node |
Java |
Medium |
| 117 |
Populating Next Right Pointers in Each Node II |
Java |
Medium |
| 118 |
Pascal’s Triangle |
Java |
Easy |
| 119 |
Pascal’s Triangle II |
Java |
Easy |
| 120 |
Triangle |
Java |
Medium |
| 121 |
Best Time to Buy and Sell Stock |
Java |
Easy |
| 122 |
Best Time to Buy and Sell Stock II |
Java |
Easy |
| 125 |
Valid Palindrome |
Java |
Easy |
| 130 |
Surrounded Regions |
Java |
Medium |
| 132 |
Palindrome Partitioning II |
Java |
Hard |
| 135 |
Candy |
Java |
Hard |
| 136 |
Single Number |
Java |
Easy |
| 141 |
Linked List Cycle |
Java |
Easy |
| 142 |
Linked List Cycle II |
Java |
Medium |
| 150 |
Evaluate Reverse Polish Notation |
Java |
Medium |
| 153 |
Find Minimum in Rotated Sorted Array |
Java |
Medium |
| 155 |
Min Stack |
Java |
Easy |
| 160 |
Intersection of Two Linked Lists |
Java |
Easy |
| 162 |
Find Peak Element |
Java |
Medium |
| 167 |
Two Sum II - Input array is sorted |
Java |
Easy |
| 168 |
Excel Sheet Column Title |
Java |
Easy |
| 169 |
Majority Element |
Java |
Easy |
| 171 |
Excel Sheet Column Number |
Java |
Easy |
| 172 |
Factorial Trailing Zeroes |
Java |
Easy |
| 173 |
Binary Search Tree Iterator |
Java |
Medium |
| 179 |
Largest Number |
Java |
Medium |
| 189 |
Rotate Array |
Java |
Medium |
| 190 |
Reverse Bits |
Java |
Easy |
| 191 |
Number of 1 Bits |
Java |
Easy |
| 198 |
House Robber |
Java |
Medium |
| 200 |
Number of Islands |
Java |
Medium |
| 202 |
Happy Number |
Java |
Easy |
| 206 |
Reverse Linked List |
Java |
Easy |
| 208 |
Implement Trie (Prefix Tree) |
Java |
Medium |
| 209 |
Minimum Size Subarray Sum |
Java |
Medium |
| 213 |
House Robber II |
Java |
Medium |
| 217 |
Contains Duplicate |
Java |
Easy |
| 219 |
Contains Duplicate II |
Java |
Easy |
| 220 |
Contains Duplicate III |
Java |
Medium |
| 224 |
Basic Calculator |
Java |
Hard |
| 226 |
Invert Binary Tree |
Java |
Easy |
| 227 |
Basic Calculator II |
Java |
Medium |
| 229 |
Majority Element II |
Java |
Easy |
| 230 |
Kth Smallest Element in a BST |
Java |
Easy |
| 231 |
Power of Two |
Java |
Easy |
| 232 |
Implement Queue using Stacks |
Java |
Easy |
| 237 |
Delete Node in a Linked List |
Java |
Easy |
| 252 |
Meeting Rooms |
Java |
Easy |
| 258 |
Add Digits |
Java |
Easy |
| 263 |
Ugly Number |
Java |
Easy |
| 264 |
Ugly Number II |
Java |
Medium |
| 268 |
Missing Number |
Java |
Easy |
| 278 |
First Bad Version |
Java |
Easy |
| 283 |
Move Zeroes |
Java |
Easy |
| 300 |
Longest Increasing Subsequence |
Java |
Medium |
| 303 |
Range Sum Query - Immutable |
Java |
Easy |
| 304 |
Range Sum Query 2D - Immutable |
Java |
Medium |
| 328 |
Odd Even Linked List |
Java |
Medium |
| 331 |
Verify Preorder Serialization of a Binary Tree |
Java |
Medium |
| 338 |
Counting Bits |
Java |
Medium |
| 342 |
Power of Four |
Java |
Medium |
| 344 |
Reverse String |
Java |
Easy |
| 354 |
Russian Doll Envelopes |
Java |
Hard |
| 367 |
Valid Perfect Square |
Java |
Easy |
| 368 |
Largest Divisible Subset |
Java |
Easy |
| 383 |
Ransom Note |
Java |
Easy |
| 387 |
First Unique Character in a String |
Java |
Easy |
| 392 |
Is Subsequence |
Java |
Easy |
| 395 |
Longest Substring with At Least K Repeating Characterse |
Java |
Medium |
| 402 |
Remove K Digits |
Java |
Medium |
| 406 |
Queue Reconstruction by Height |
Java |
Medium |
| 413 |
Arithmetic Slices |
Java |
Medium |
| 414 |
Third Maximum Number |
Java |
Easy |
| 435 |
Non-overlapping Intervals |
Java |
Medium |
| 438 |
Find All Anagrams in a String |
Java |
Medium |
| 441 |
Arranging Coins |
Java |
Easy |
| 442 |
Find All Duplicates in an Array |
Java |
Easy |
| 448 |
Find All Numbers Disappeared in an Array |
Java |
Easy |
| 451 |
Sort Characters By Frequency |
Java |
Medium |
| 452 |
Minimum Number of Arrows to Burst Balloons |
Java |
Medium |
| 455 |
Assign Cookies |
Java |
Easy |
| 456 |
132 Pattern |
Java |
Easy |
| 476 |
Number Complement |
Java |
Easy |
| 485 |
Max Consecutive Ones |
Java |
Easy |
| 496 |
Next Greater Element I |
Java |
Easy |
| 503 |
Next Greater Element II |
Java |
Medium |
| 509 |
Fibonacci Number |
Java |
Easy |
| 518 |
Coin Change 2 |
Java |
Medium |
| 520 |
Detect Capital |
Java |
Easy |
| 521 |
Longest Uncommon Subsequence I |
Java |
Easy |
| 525 |
Contiguous Array |
Java |
Easy |
| 528 |
Random Pick with Weight |
Java |
Medium |
| 532 |
K-diff Pairs in an Array |
Java |
Easy |
| 540 |
Single Element in a Sorted Array |
Java |
Medium |
| 542 |
01 Matrix |
Java |
Medium |
| 547 |
Number of Provinces |
Java |
Medium |
| 557 |
Reverse Words in a String III |
Java |
Medium |
| 561 |
Array Partition I |
Java |
Easy |
| 566 |
Reshape the Matrix |
Java |
Easy |
| 567 |
Permutation in String |
Java |
Medium |
| 572 |
Subtree of Another Tree |
Java |
Medium |
| 581 |
Shortest Unsorted Continuous Subarray |
Java |
Easy |
| 599 |
Minimum Index Sum of Two Lists |
Java |
Easy |
| 605 |
Can Place Flowers |
Java |
Easy |
| 617 |
Merge Two Binary Trees |
Java |
Easy |
| 665 |
Non-decreasing Array |
Java |
Medium |
| 673 |
Number of Longest Increasing Subsequence |
Java |
Medium |
| 695 |
Max Area of Island |
Java |
Medium |
| 697 |
Degree of an Array |
Java |
Easy |
| 700 |
Search in a Binary Search Tree |
Java |
Easy |
| 704 |
Binary Search |
Java |
Easy |
| 705 |
Design HashSet |
Java |
Easy |
| 713 |
Subarray Product Less Than K |
Java |
Medium |
| 724 |
Find Pivot Index |
Java |
Easy |
| 733 |
Flood Fill |
Java |
Easy |
| 746 |
Min Cost Climbing Stairs |
Java |
Easy |
| 747 |
Largest Number At Least Twice of Others |
Java |
Easy |
| 763 |
Partition Labels |
Java |
Medium |
| 766 |
Toeplitz Matrix |
Java |
Easy |
| 771 |
Jewels and Stones |
Java |
Easy |
| 783 |
Minimum Distance Between BST Nodes |
Java |
Easy |
| 784 |
Letter Case Permutation |
Java |
Medium |
| 797 |
All Paths From Source to Target |
Java |
Medium |
| 830 |
Positions of Large Groups |
Java |
Easy |
| 832 |
Flipping an Image |
Java |
Easy |
| 840 |
Magic Squares In Grid |
Java |
Easy |
| 844 |
Backspace String Compare |
Java |
Easy |
| 849 |
Maximize Distance to Closest Person |
Java |
Easy |
| 867 |
Transpose Matrix |
Java |
Easy |
| 876 |
Middle of the Linked List |
Java |
Easy |
| 888 |
Transpose Matrix |
Java |
Easy |
| 896 |
Monotonic Array |
Java |
Easy |
| 897 |
Increasing Order Search Tree |
Java |
Easy |
| 905 |
Sort Array By Parity |
Java |
Easy |
| 914 |
X of a Kind in a Deck of Cards |
Java |
Easy |
| 918 |
Maximum Sum Circular Subarray |
Java |
Medium |
| 922 |
Sort Array By Parity II |
Java |
Easy |
| 938 |
Range Sum of BST |
Java |
Easy |
| 941 |
Valid Mountain Array |
Java |
Easy |
| 977 |
Squares of a Sorted Array |
Java |
Easy |
| 978 |
Longest Turbulent Subarray |
Java |
Medium |
| 985 |
Sum of Even Numbers After Queries |
Java |
Easy |
| 986 |
Interval List Intersections |
Java |
Easy |
| 989 |
Add to Array-Form of Integer |
Java |
Easy |
| 992 |
Subarrays with K Different Integers |
Java |
Hard |
| 993 |
Cousins in Binary Tree |
Java |
Easy |
| 994 |
Rotting Oranges |
Java |
Medium |
| 997 |
Find the Town Judge |
Java |
Easy |
| 1004 |
Max Consecutive Ones III |
Java |
Medium |
| 1006 |
Clumsy Factorial |
Java |
Medium |
| 1008 |
Construct Binary Search Tree from Preorder Traversal |
Java |
Medium |
| 1010 |
Pairs of Songs With Total Durations Divisible by 60 |
Java |
Easy |
| 1011 |
Capacity To Ship Packages Within D Days |
Java |
Medium |
| 1013 |
Partition Array Into Three Parts With Equal Sum |
Java |
Easy |
| 1020 |
Number of Enclaves |
Java |
Medium |
| 1029 |
Two City Scheduling |
Java |
Easy |
| 1035 |
Uncrossed Lines |
Java |
Medium |
| 1047 |
Remove All Adjacent Duplicates In String |
Java |
Medium |
| 1051 |
Height Checker |
Java |
Easy |
| 1052 |
Grumpy Bookstore Owner |
Java |
Medium |
| 1089 |
Duplicate Zeros |
Java |
Easy |
| 1091 |
Shortest Path in Binary Matrix |
Java |
Medium |
| 1094 |
Car Pooling |
Java |
Medium |
| 1122 |
Relative Sort Array |
Java |
Easy |
| 1160 |
Find Words That Can Be Formed by Characters |
Java |
Easy |
| 1178 |
Number of Valid Words for Each Puzzle |
Java |
Hard |
| 1232 |
Check If It Is a Straight Line |
Java |
Easy |
| 1277 |
Count Square Submatrices with All Ones |
Java |
Medium |
| 1295 |
Find Numbers with Even Number of Digits |
Java |
Easy |
| 1290 |
Replace Elements with Greatest Element on Right Side |
Java |
Easy |
| 1342 |
Number of Steps to Reduce a Number to Zero |
Java |
Easy |
| 1346 |
Check If N and Its Double Exist |
Java |
Easy |
| 1380 |
Lucky Numbers in a Matrix |
Java |
Easy |
| 1394 |
Find Lucky Integer in an Array |
Java |
Easy |
| 1414 |
Find the Minimum Number of Fibonacci Numbers Whose Sum Is K |
Java |
Medium |
| 1438 |
Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit |
Java |
Easy |
| 1447 |
Simplified Fractions |
Java |
Medium |
| 1468 |
XOR Operation in an Array |
Java |
Easy |
| 1603 |
Design Parking System |
Java |
Easy |
| 2006 |
Count Number of Pairs With Absolute Difference K |
Java |
Easy |
| 2055 |
Plates Between Candles |
Java |
Easy |
| 2104 |
Sum of Subarray Ranges |
Java |
Medium |