LeetCode #1
Easy
Array
15 min
All categoriesValid Parentheses Merge Two Sorted Lists Best Time to Buy and Sell Stock Valid Palindrome Invert Binary Tree Valid Anagram Binary Search Flood Fill Maximum Subarray Lowest Common Ancestor of a Binary Search Tree Insert Interval 01 Matrix K Closest Points to Origin Balanced Binary Tree Linked List Cycle Implement Queue using Stacks First Bad Version Ransom Note Longest Substring Without Repeating Characters 3Sum Binary Tree Level Order Traversal Clone Graph Evaluate Reverse Polish Notation Course Schedule Implement Trie (Prefix Tree) Coin Change Product of Array Except Self Climbing Stairs Longest Palindrome Min Stack Reverse Linked List Validate Binary Search Tree Number of Islands Rotting Oranges Search in Rotated Sorted Array Combination Sum Permutations Merge Intervals Lowest Common Ancestor of a Binary Tree Time Based Key-Value Store Minimum Window Substring Serialize and Deserialize Binary Tree Trapping Rain Water Find Median from Data Stream Majority Element Add Binary Diameter of Binary Tree Middle of the Linked List Accounts Merge Sort Colors Word Break Partition Equal Subset Sum String to Integer (atoi) Spiral Matrix Subsets Binary Tree Right Side View Longest Palindromic Substring Word Ladder Basic Calculator Maximum Profit in Job Scheduling Merge k Sorted Lists Largest Rectangle in Histogram Maximum Depth of Binary Tree Contains Duplicate Unique Paths Construct Binary Tree from Preorder and Inorder Traversal Container With Most Water Letter Combinations of a Phone Number Word Search Find All Anagrams in a String Minimum Height Trees Task Scheduler LRU Cache Kth Smallest Element in a BST Daily Temperatures House Robber Meeting Rooms Roman to Integer Backspace String Compare Gas Station Next Permutation Valid Sudoku Group Anagrams Maximum Product Subarray Design Add and Search Words Data Structure Pacific Atlantic Water Flow Remove Nth Node From End of List Shortest Path to Get Food Find the Duplicate Number Top K Frequent Words Binary Tree Maximum Path Sum Maximum Frequency Stack Counting Bits Longest Increasing Subsequence Graph Valid Tree Course Schedule II Swap Nodes in Pairs Path Sum II Longest Consecutive Sequence Rotate Array Odd Even Linked List Decode String Contiguous Array Maximum Width of Binary Tree Find K Closest Elements Longest Repeating Character Replacement Median of Two Sorted Arrays Same Tree Number of 1 Bits Longest Common Prefix Inorder Successor in BST Jump Game Add Two Numbers Generate Parentheses Sort List Number of Connected Components in an Undirected Graph Minimum Knight Moves Subarray Sum Equals K Asteroid Collision Random Pick with Weight Kth Largest Element in an Array Longest Increasing Path in a Matrix Longest Valid Parentheses Design In-Memory File System Employee Free Time Single Number Palindrome Linked List Move Zeroes Maximal Square Rotate Image Binary Tree Zigzag Level Order Traversal Design Hit Counter Path Sum III Pow(x, n) Search a 2D Matrix Largest Number Word Search II Alien Dictionary Bus Routes Symmetric Tree Missing Number Decode Ways Meeting Rooms II Reverse Integer Set Matrix Zeroes Reorder List Encode and Decode Strings Cheapest Flights Within K Stops All Nodes Distance K in Binary Tree Sliding Window Maximum Palindrome Number Convert Sorted Array to Binary Search Tree Reverse Bits Subtree of Another Tree Squares of a Sorted Array 3Sum Closest Rotate List Find Minimum in Rotated Sorted Array Basic Calculator II Combination Sum IV Insert Delete GetRandom O(1) Non-overlapping Intervals Palindrome Pairs Reverse Nodes in k-Group Sudoku Solver First Missing Positive N-Queens Smallest Range Covering Elements from K Lists
Category
DSA & Algorithms (Blind 169)
169 problem set covering every 75 problems plus deeper coverage across all major patterns.
169 questions
169 of 169
Two Sum
LeetCode #20
Easy
Stack
20 min
LeetCode #21
Easy
Linked List
20 min
LeetCode #121
Easy
Array
20 min
LeetCode #125
Easy
String
15 min
LeetCode #226
Easy
Binary Tree
15 min
LeetCode #242
Easy
String
15 min
LeetCode #792
Easy
Binary Search
15 min
LeetCode #733
Easy
Graph
20 min
LeetCode #53
Medium
Dynamic Programming
20 min
LeetCode #235
Easy
Binary Search Tree
20 min
LeetCode #57
Medium
Array
25 min
LeetCode #542
Medium
Graph
30 min
LeetCode #1014
Medium
Heap
30 min
LeetCode #110
Easy
Binary Tree
15 min
LeetCode #141
Easy
Linked List
20 min
LeetCode #232
Easy
Stack
20 min
LeetCode #278
Easy
Binary Search
20 min
LeetCode #383
Easy
Hash Table
15 min
LeetCode #3
Medium
String
30 min
LeetCode #15
Medium
Array
30 min
LeetCode #102
Medium
Binary Tree
20 min
LeetCode #133
Medium
Graph
25 min
LeetCode #150
Medium
Stack
30 min
LeetCode #207
Medium
Graph
30 min
LeetCode #208
Medium
Trie
35 min
LeetCode #322
Medium
Dynamic Programming
25 min
LeetCode #238
Medium
Array
30 min
LeetCode #70
Easy
Dynamic Programming
20 min
LeetCode #409
Easy
String
20 min
LeetCode #155
Medium
Stack
20 min
LeetCode #206
Easy
Linked List
20 min
LeetCode #98
Medium
Binary Search Tree
20 min
LeetCode #200
Medium
Graph
25 min
LeetCode #1036
Medium
Graph
30 min
LeetCode #33
Medium
Binary Search
30 min
LeetCode #39
Medium
Array
30 min
LeetCode #46
Medium
Recursion
30 min
LeetCode #56
Medium
Array
30 min
LeetCode #236
Medium
Binary Tree
25 min
LeetCode #1023
Medium
Binary Search
35 min
LeetCode #76
Hard
String
30 min
LeetCode #297
Hard
Binary Tree
40 min
LeetCode #42
Hard
Stack
35 min
LeetCode #295
Hard
Heap
30 min
LeetCode #169
Easy
Array
20 min
LeetCode #67
Easy
Binary
15 min
LeetCode #543
Easy
Binary Tree
30 min
LeetCode #908
Easy
Linked List
20 min
LeetCode #721
Medium
Graph
30 min
LeetCode #75
Medium
Array
25 min
LeetCode #139
Medium
Trie
30 min
LeetCode #416
Medium
Dynamic Programming
30 min
LeetCode #8
Medium
String
25 min
LeetCode #54
Medium
Matrix
25 min
LeetCode #78
Medium
Recursion
30 min
LeetCode #199
Medium
Binary Tree
20 min
LeetCode #5
Medium
String
25 min
LeetCode #127
Hard
Graph
45 min
LeetCode #224
Hard
Stack
40 min
LeetCode #1352
Hard
Binary Search
45 min
LeetCode #23
Hard
Heap
30 min
LeetCode #84
Hard
Stack
35 min
LeetCode #104
Easy
Binary Tree
15 min
LeetCode #217
Easy
Array
15 min
LeetCode #62
Medium
Dynamic Programming
20 min
LeetCode #105
Medium
Binary Tree
25 min
LeetCode #11
Medium
Array
35 min
LeetCode #17
Medium
Recursion
30 min
LeetCode #79
Medium
Graph
30 min
LeetCode #438
Medium
String
30 min
LeetCode #310
Medium
Graph
30 min
LeetCode #621
Medium
Heap
35 min
LeetCode #146
Medium
Linked List
30 min
LeetCode #230
Medium
Binary Search Tree
25 min
LeetCode #739
Medium
Stack
30 min
LeetCode #198
Medium
Dynamic Programming
25 min
LeetCode #252
Easy
Array
20 min
LeetCode #13
Easy
Math
20 min
LeetCode #874
Easy
Stack
15 min
LeetCode #134
Medium
Array
30 min
LeetCode #31
Medium
Recursion
30 min
LeetCode #36
Medium
Matrix
35 min
LeetCode #49
Medium
String
25 min
LeetCode #152
Medium
Dynamic Programming
30 min
LeetCode #211
Medium
Trie
35 min
LeetCode #417
Medium
Graph
30 min
LeetCode #19
Medium
Linked List
20 min
LeetCode #550
Medium
Graph
30 min
LeetCode #287
Medium
Binary
20 min
LeetCode #692
Medium
Heap
30 min
LeetCode #124
Hard
Binary Tree
35 min
LeetCode #931
Hard
Stack
40 min
LeetCode #338
Easy
Binary
15 min
LeetCode #300
Medium
Dynamic Programming
30 min
LeetCode #261
Medium
Graph
30 min
LeetCode #210
Medium
Graph
35 min
LeetCode #24
Medium
Linked List
25 min
LeetCode #113
Medium
Binary Tree
25 min
LeetCode #128
Medium
Array
30 min
LeetCode #189
Medium
Array
25 min
LeetCode #328
Medium
Linked List
25 min
LeetCode #394
Medium
Stack
30 min
LeetCode #525
Medium
Array
30 min
LeetCode #662
Medium
Binary Tree
20 min
LeetCode #658
Medium
Heap
30 min
LeetCode #424
Medium
String
30 min
LeetCode #4
Hard
Binary Search
40 min
LeetCode #100
Easy
Binary Tree
20 min
LeetCode #191
Easy
Binary
15 min
LeetCode #14
Easy
String
20 min
LeetCode #285
Medium
Binary Search Tree
30 min
LeetCode #55
Medium
Dynamic Programming
20 min
LeetCode #2
Medium
Linked List
25 min
LeetCode #22
Medium
Recursion
25 min
LeetCode #148
Medium
Linked List
25 min
LeetCode #323
Medium
Graph
30 min
LeetCode #1142
Medium
Graph
35 min
LeetCode #560
Medium
Array
35 min
LeetCode #735
Medium
Stack
30 min
LeetCode #912
Medium
Math
25 min
LeetCode #215
Medium
Heap
30 min
LeetCode #329
Hard
Graph
40 min
LeetCode #32
Hard
Stack
35 min
LeetCode #588
Hard
Trie
40 min
LeetCode #761
Hard
Array
35 min
LeetCode #136
Easy
Binary
15 min
LeetCode #234
Easy
Linked List
20 min
LeetCode #283
Easy
Array
20 min
LeetCode #221
Medium
Dynamic Programming
30 min
LeetCode #48
Medium
Matrix
25 min
LeetCode #103
Medium
Binary Tree
25 min
LeetCode #362
Medium
Queue
30 min
LeetCode #437
Medium
Binary Tree
35 min
LeetCode #50
Medium
Math
20 min
LeetCode #74
Medium
Binary Search
30 min
LeetCode #179
Medium
String
20 min
LeetCode #212
Hard
Graph
40 min
LeetCode #269
Hard
Graph
45 min
LeetCode #833
Hard
Graph
45 min
LeetCode #101
Easy
Binary Tree
20 min
LeetCode #268
Easy
Binary
15 min
LeetCode #91
Medium
Dynamic Programming
25 min
LeetCode #253
Medium
Array
30 min
LeetCode #7
Medium
Math
25 min
LeetCode #73
Medium
Matrix
25 min
LeetCode #143
Medium
Linked List
25 min
LeetCode #271
Medium
String
25 min
LeetCode #803
Medium
Graph
45 min
LeetCode #893
Medium
Binary Tree
25 min
LeetCode #239
Hard
Array
35 min
LeetCode #9
Easy
Math
15 min
LeetCode #108
Easy
Binary Search Tree
20 min
LeetCode #190
Easy
Binary
15 min
LeetCode #572
Easy
Binary Tree
20 min
LeetCode #1019
Easy
Array
20 min
LeetCode #16
Medium
Array
30 min
LeetCode #61
Medium
Linked List
25 min
LeetCode #153
Medium
Binary Search
30 min
LeetCode #227
Medium
Stack
30 min
LeetCode #377
Medium
Dynamic Programming
35 min
LeetCode #380
Medium
Hash Table
20 min
LeetCode #435
Medium
Array
20 min
LeetCode #336
Hard
String
40 min
LeetCode #25
Hard
Linked List
35 min
LeetCode #37
Hard
Matrix
40 min
LeetCode #41
Hard
Hash Table
35 min
LeetCode #51
Hard
Recursion
40 min
LeetCode #632
Hard
Heap
40 min