| 217 |
Contains Duplicate |
Arrays & Hashing |
python3 |
| 242 |
Valid Anagram |
Arrays & Hashing |
python3 |
| 1 |
Two Sum |
Arrays & Hashing |
java, python3 |
| 49 |
Group Anagrams |
Arrays & Hashing |
python3 |
| 347 |
Top K Frequent Elements |
Arrays & Hashing |
python3 |
| 238 |
Product of Array Except Self |
Arrays & Hashing |
python3 |
| 36 |
Valid Sudoku |
Arrays & Hashing |
python3 |
| 271 |
Encode and Decode Strings |
Arrays & Hashing |
python3 |
| 128 |
Longest Consecutive Sequence |
Arrays & Hashing |
python3 |
| 125 |
Valid Palindrome |
Two Pointers |
python3 |
| 167 |
Two Sum II |
Two Pointers |
python3 |
| 15 |
3Sum |
Two Pointers |
java, python3 |
| 11 |
Container with Most Water |
Two Pointers |
java, python3 |
| 42 |
Trapping Rain Water |
Two Pointers |
python3 |
| 121 |
Best Time to Buy & Sell Stock |
Sliding Window |
python3 |
| 3 |
Longest Substring Without Repeating Characters |
Sliding Window |
java, python3 |
| 424 |
Longest Repeating Character Replacement |
Sliding Window |
python3 |
| 567 |
Permutation in String |
Sliding Window |
python3 |
| 76 |
Minimum Window Substring |
Sliding Window |
python3 |
| 239 |
Sliding Window Maximum |
Sliding Window |
|
| 20 |
Valid Parentheses |
Stack |
java, python3 |
| 155 |
Min Stack |
Stack |
python3 |
| 150 |
Evaluate Reverse Polish Notation |
Stack |
python3 |
| 22 |
Generate Parentheses |
Stack |
java, python3 |
| 739 |
Daily Temperatures |
Stack |
python3 |
| 853 |
Car Fleet |
Stack |
python3 |
| 84 |
Largest Rectangle in Histogram |
Stack |
python3 |
| 704 |
Binary Search |
Binary Search |
python3 |
| 74 |
Search a 2D Matrix |
Binary Search |
python3 |
| 875 |
Koko Eating Bananas |
Binary Search |
python3 |
| 33 |
Search Rotated Sorted Array |
Binary Search |
java, python3 |
| 153 |
Find Minimum in Rotated Sorted Array |
Binary Search |
python3 |
| 981 |
Time Based Key-Value Store |
Binary Search |
python3 |
| 4 |
Find Median of Two Sorted Arrays |
Binary Search |
java |
| 206 |
Reverse Linked List |
Linked List |
python3 |
| 21 |
Merge Two Linked Lists |
Linked List |
java, python3 |
| 143 |
Reorder List |
Linked List |
python3 |
| 19 |
Remove Nth Node from End of List |
Linked List |
java, python3 |
| 138 |
Copy List with Random Pointer |
Linked List |
python3 |
| 2 |
Add Two Numbers |
Linked List |
java, python3 |
| 141 |
Linked List Cycle |
Linked List |
python3 |
| 287 |
Find the Duplicate Number |
Linked List |
python3 |
| 146 |
LRU Cache |
Linked List |
python3 |
| 23 |
Merge K Sorted Lists |
Linked List |
java, python3 |
| 25 |
Reverse Nodes in K-Group |
Linked List |
|
| 226 |
Invert Binary Tree |
Trees |
python3 |
| 104 |
Maximum Depth of Binary Tree |
Trees |
python3 |
| 543 |
Diameter of a Binary Tree |
Trees |
python3 |
| 110 |
Balanced Binary Tree |
Trees |
python3 |
| 100 |
Same Tree |
Trees |
python3 |
| 572 |
Subtree of Another Tree |
Trees |
|
| 235 |
Lowest Common Ancestor of a BST |
Trees |
python3 |
| 102 |
Binary Tree Level Order Traversal |
Trees |
python3 |
| 199 |
Binary Tree Right Side View |
Trees |
python3 |
| 1448 |
Count Good Nodes in a Binary Tree |
Trees |
|
| 98 |
Validate Binary Search Tree |
Trees |
|
| 230 |
Kth Smallest Element in a BST |
Trees |
|
| 105 |
Construct Tree from Preorder and Inorder Traversal |
Trees |
python3 |
| 124 |
Binary Tree Max Path Sum |
Trees |
|
| 297 |
Serialize and Deserialize Binary Tree |
Trees |
python3 |
| 208 |
Implement Trie |
Tries |
|
| 211 |
Design Add and Search Word Data Structure |
Tries |
|
| 212 |
Word Search II |
Tries |
|
| 703 |
Kth Largest Element in a Stream |
Heap / Priority Queue |
python3 |
| 1046 |
Last Stone Weight |
Heap / Priority Queue |
python3 |
| 973 |
K Closest Points to Origin |
Heap / Priority Queue |
python3 |
| 215 |
Kth Largest Element in an Array |
Heap / Priority Queue |
python3 |
| 621 |
Task Scheduler |
Heap / Priority Queue |
python3 |
| 355 |
Design Twitter |
Heap / Priority Queue |
|
| 295 |
Find Median from Data Stream |
Heap / Priority Queue |
|
| 78 |
Subsets |
Backtracking |
python3 |
| 39 |
Combination Sum |
Backtracking |
java, python3 |
| 46 |
Permutations |
Backtracking |
java, python3 |
| 90 |
Subsets II |
Backtracking |
python3 |
| 40 |
Combination Sum II |
Backtracking |
java, python3 |
| 79 |
Word Search |
Backtracking |
python3 |
| 131 |
Palindrome Partitioning |
Backtracking |
python3 |
| 17 |
Letter Combinations of a Phone Number |
Backtracking |
java, python3 |
| 51 |
N-Queens |
Backtracking |
python3 |
| 200 |
Number of Islands |
Graphs |
python3 |
| 133 |
Clone Graph |
Graphs |
|
| 695 |
Max Area of Island |
Graphs |
|
| 417 |
Pacific Atlantic Waterflow |
Graphs |
|
| 130 |
Surrounded Regions |
Graphs |
|
| 994 |
Rotting Oranges |
Graphs |
|
| 286 |
Walls and Gates |
Graphs |
|
| 207 |
Course Schedule |
Graphs |
|
| 210 |
Course Schedule II |
Graphs |
|
| 684 |
Redundant Connection |
Graphs |
|
| 323 |
Number of Connected Components in Graph |
Graphs |
|
| 261 |
Graph Valid Tree |
Graphs |
|
| 127 |
Word Ladder |
Graphs |
|
| 332 |
Reconstruct Itinerary |
Advanced Graphs |
|
| 1584 |
Min Cost to Connect all Points |
Advanced Graphs |
|
| 743 |
Network Delay Time |
Advanced Graphs |
|
| 778 |
Swim in Rising Water |
Advanced Graphs |
|
| 269 |
Alien Dictionary |
Advanced Graphs |
|
| 787 |
Cheapest Flights Within K Stops |
Advanced Graphs |
|
| 70 |
Climbing Stairs |
1-D Dynamic Programming |
java, python3 |
| 746 |
Min Cost Climbing Stairs |
1-D Dynamic Programming |
python3 |
| 198 |
House Robber |
1-D Dynamic Programming |
python3 |
| 213 |
House Robber II |
1-D Dynamic Programming |
python3 |
| 5 |
Longest Palindromic Substring |
1-D Dynamic Programming |
java, python3 |
| 647 |
Palindromic Substrings |
1-D Dynamic Programming |
python3 |
| 91 |
Decode Ways |
1-D Dynamic Programming |
python3 |
| 322 |
Coin Change |
1-D Dynamic Programming |
python3 |
| 152 |
Maximum Product Subarray |
1-D Dynamic Programming |
python3 |
| 139 |
Word Break |
1-D Dynamic Programming |
python3 |
| 300 |
Longest Increasing Subsequence |
1-D Dynamic Programming |
python3 |
| 416 |
Partition Equal Subset Sum |
1-D Dynamic Programming |
python3 |
| 62 |
Unique Paths |
2-D Dynamic Programming |
python3 |
| 1143 |
Longest Common Subsequence |
2-D Dynamic Programming |
python3 |
| 309 |
Best Time to Buy/Sell Stock With Cooldown |
2-D Dynamic Programming |
python3 |
| 518 |
Coin Change II |
2-D Dynamic Programming |
python3 |
| 494 |
Target Sum |
2-D Dynamic Programming |
python3 |
| 97 |
Interleaving String |
2-D Dynamic Programming |
python3 |
| 329 |
Longest Increasing Path in a Matrix |
2-D Dynamic Programming |
|
| 115 |
Distinct Subsequences |
2-D Dynamic Programming |
|
| 72 |
Edit Distance |
2-D Dynamic Programming |
|
| 312 |
Burst Balloons |
2-D Dynamic Programming |
|
| 10 |
Regular Expression Matching |
2-D Dynamic Programming |
java |
| 53 |
Maximum Subarray |
Greedy |
java, python3 |
| 55 |
Jump Game |
Greedy |
java, python3 |
| 45 |
Jump Game II |
Greedy |
java, python3 |
| 134 |
Gas Station |
Greedy |
python3 |
| 846 |
Hand of Straights |
Greedy |
python3 |
| 1899 |
Merge Triplets to Form Target Triplet |
Greedy |
python3 |
| 763 |
Partition Labels |
Greedy |
python3 |
| 678 |
Valid Parenthesis String |
Greedy |
python3 |
| 57 |
Insert Interval |
Intervals |
python3 |
| 56 |
Merge Intervals |
Intervals |
python3 |
| 435 |
Non-Overlapping Intervals |
Intervals |
|
| 252 |
Meeting Rooms |
Intervals |
|
| 253 |
Meeting Rooms II |
Intervals |
|
| 1851 |
Minimum Interval to Include Each Query |
Intervals |
|
| 48 |
Rotate Image |
Math & Geometry |
java |
| 54 |
Spiral Matrix |
Math & Geometry |
|
| 73 |
Set Matrix Zeroes |
Math & Geometry |
|
| 202 |
Happy Number |
Math & Geometry |
|
| 66 |
Plus One |
Math & Geometry |
|
| 50 |
Pow(x, n) |
Math & Geometry |
|
| 43 |
Multiply Strings |
Math & Geometry |
|
| 2013 |
Detect Squares |
Math & Geometry |
|
| 136 |
Single Number |
Bit Manipulation |
|
| 191 |
Number of 1 Bits |
Bit Manipulation |
|
| 338 |
Counting Bits |
Bit Manipulation |
|
| 190 |
Reverse Bits |
Bit Manipulation |
|
| 268 |
Missing Number |
Bit Manipulation |
|
| 371 |
Sum of Two Integers |
Bit Manipulation |
|
| 7 |
Reverse Integer |
Bit Manipulation |
java |