| 1 |
Two Sum |
link |
Easy |
Array, Dictionary |
| 1 |
Add Two Numbers |
link |
Medium |
Linked List |
| 3 |
Longest Substring Without Repeating Characters |
link |
Medium |
Array, Sliding Window |
| 11 |
Container With Most Water |
link |
Medium |
Array, Two Pointer |
| 15 |
3Sum |
link |
Medium |
Array, Two Pointer |
| 19 |
Remove Nth Node From End Of List |
link |
Medium |
Linked List |
| 20 |
Valid Parentheses |
link |
Easy |
Array, Dictionary, Stack |
| 21 |
Merge Two Sorted Lists |
link |
Easy |
Linked Lists |
| 22 |
Generate Parentheses |
link |
Medium |
Array, Stack |
| 23 |
Merge k Sorted Lists |
link |
Hard |
Linked Lists, Merge Sort |
| 26 |
Remove Duplicates From Sorted Array |
link |
Easy |
Array |
| 27 |
Remove Element |
link |
Easy |
Array |
| 33 |
Search In Rotated Sorted Array |
link |
Medium |
Binary Search |
| 36 |
Valid Sudoku |
link |
Medium |
Array |
| 39 |
Combination Sum |
link |
Medium |
Backtracking |
| 40 |
Combination Sum II |
link |
Medium |
Backtracking |
| 46 |
Permutations |
link |
Medium |
Backtracking |
| 49 |
Group Anagram |
link |
Medium |
Array, Dictionary |
| 74 |
Search A 2D Matrix |
link |
Medium |
Binary Search |
| 78 |
Subsets |
link |
Medium |
Backtracking |
| 88 |
Merge Sorted Array |
link |
Easy |
Array |
| 90 |
Subsets II |
link |
Medium |
Backtracking |
| 98 |
Validate Binary Search Tree |
link |
Medium |
Tree, DFS, Array |
| 100 |
Same Tree |
link |
Easy |
Tree, DFS |
| 102 |
Binary Tree Level Order Traversal |
link |
Medium |
Tree, BFS |
| 105 |
Construct Binary Tree From Preorder And Inorder Traversal |
link |
Medium |
Tree, DFS, Array |
| 110 |
Balanced Binary Tree |
link |
Easy |
Tree, DFS |
| 121 |
Best Time to Buy and Sell Stock |
link |
Easy |
Array, Sliding Window |
| 124 |
Binary Tree Maximum Path Sum |
link |
Hard |
Tree, DFS |
| 125 |
Valid Palindrome |
link |
Easy |
Array, Two Pointers |
| 128 |
Longest Consecutive Sequence |
link |
Medium |
Array |
| 141 |
Linked List Cycle |
link |
Easy |
Linked List |
| 143 |
Reorder List |
link |
Medium |
Linked List |
| 150 |
Evaluate Reverse Polish Notation |
link |
Medium |
Stack |
| 153 |
Find Minimum In Rotated Sorted Array |
link |
Medium |
Binary Search |
| 155 |
Min Stack |
link |
Medium |
Stack |
| 167 |
Two Sum II - Input Array Is Sorted |
link |
Medium |
Array, Two Pointers |
| 199 |
Binary Tree Right Side View |
link |
Medium |
Tree, BFS |
| 215 |
Kth Largest Element In An Array |
link |
Medium |
Max Heap |
| 217 |
Contains Duplicate |
link |
Easy |
Array, Dictionary |
| 206 |
Reverse Linked List |
link |
Easy |
Linked List |
| 226 |
Invert Binary Tree |
link |
Easy |
Tree, DFS |
| 230 |
Kth Smallest Element In A BST |
link |
Medium |
Tree, DFS |
| 235 |
Lowest Common Ancestor Of A Binary Search Tree |
link |
Medium |
Tree, Binary Search |
| 238 |
Product of Array Except Self |
link |
Medium |
Array |
| 242 |
Valid Anagram |
link |
Easy |
Array, Dictionary |
| 287 |
Find The Duplicate Number |
link |
Medium |
Linked List, Two Pointers |
| 347 |
Top K Frequent Elements |
link |
Medium |
Array, Dictionary |
| 424 |
Longest Repeating Character Replacement |
link |
Medium |
Array, Dictionary, Sliding Window |
| 543 |
Diameter Of Binary Tree |
link |
Easy |
Tree, DFS |
| 567 |
Permutation In String |
link |
Medium |
Array, Dictionary, Sliding Window |
| 572 |
Subtree Of Another Tree |
link |
Easy |
Tree, DFS |
| 739 |
Daily Temperatures |
link |
Medium |
Array, Stack |
| 703 |
Kth Largest Element In A Stream |
link |
Easy |
Min Heap |
| 704 |
Binary Search |
link |
Easy |
Binary Search |
| 853 |
Car Fleet |
link |
Medium |
Array, Stack |
| 875 |
Koko Eating Bananas |
link |
Medium |
Binary Search |
| 973 |
K Closet Points To Origin |
link |
Medium |
Min Heap |
| 1046 |
Last Stone Weight |
link |
Easy |
Min Heap |
| 1448 |
Count Good Nodes In Binary Tree |
link |
Medium |
Tree, DFS |