Advanced Algorithms Visualizer

Step-by-step execution, multi-lingual narration, and code highlighting.

Open Advanced Visualizer

Blind 75 Must-Do Questions

Top 75 LeetCode questions for interview prep

Progress: 0 / 680%
17
Easy
44
Medium
7
Hard
0
Solved

1. Contains Duplicate

Arrays & Hashing
Easy

2. Two Sum

Arrays & Hashing
Easy

3. Top K Frequent Elements

Arrays & Hashing
Medium

4. Encode and Decode Strings

Arrays & Hashing
Medium

5. Product of Array Except Self

Arrays & Hashing
Medium

6. Valid Sudoku

Arrays & Hashing
Medium

7. Longest Consecutive Sequence

Arrays & Hashing
Medium

8. Valid Palindrome

Two Pointers
Easy

9. 3Sum

Two Pointers
Medium

10. Container With Most Water

Two Pointers
Medium

11. Trapping Rain Water

Two Pointers
Hard

12. Valid Parentheses

Stack
Easy

13. Search a 2D Matrix

Binary Search
Medium

14. Reverse Linked List

Linked List
Easy

15. Merge Two Sorted Lists

Linked List
Easy

16. Linked List Cycle

Linked List
Easy

17. Reorder List

Linked List
Medium

18. Remove Nth Node From End of List

Linked List
Medium

19. Merge K Sorted Lists

Linked List
Hard

20. Invert Binary Tree

Trees
Easy

21. Maximum Depth of Binary Tree

Trees
Easy

22. Same Tree

Trees
Easy

23. Subtree of Another Tree

Trees
Easy

24. Lowest Common Ancestor of a Binary Search Tree

Trees
Medium

25. Binary Tree Level Order Traversal

Trees
Medium

26. Validate Binary Search Tree

Trees
Medium

27. Kth Smallest Element In a Bst

Trees
Medium

28. Construct Binary Tree From Preorder And Inorder Traversal

Trees
Medium

29. Binary Tree Maximum Path Sum

Trees
Hard

30. Serialize And Deserialize Binary Tree

Trees
Hard

31. Find Median From Data Stream

Heap / Priority Queue
Hard

32. Implement Trie Prefix Tree

Tries
Medium

33. Design Add And Search Words Data Structure

Tries
Medium

34. Word Search II

Tries
Hard

35. Number of Islands

Graphs
Medium

36. Clone Graph

Graphs
Medium

37. Pacific Atlantic Water Flow

Graphs
Medium

38. Course Schedule

Graphs
Medium

39. Course Schedule II

Graphs
Medium

40. Graph Valid Tree

Graphs
Medium

41. Alien Dictionary

Advanced Graphs
Hard

42. Climbing Stairs

1-D Dynamic Programming
Easy

43. House Robber

1-D Dynamic Programming
Medium

44. House Robber II

1-D Dynamic Programming
Medium

45. Decode Ways

1-D Dynamic Programming
Medium

46. Coin Change

1-D Dynamic Programming
Medium

47. Maximum Product Subarray

1-D Dynamic Programming
Medium

48. Word Break

1-D Dynamic Programming
Medium

49. Longest Increasing Subsequence

1-D Dynamic Programming
Medium

50. Unique Paths

2-D Dynamic Programming
Medium

51. Longest Common Subsequence

2-D Dynamic Programming
Medium

52. Coin Change II

2-D Dynamic Programming
Medium

53. Maximum Subarray

Greedy
Medium

54. Jump Game

Greedy
Medium

55. Jump Game II

Greedy
Medium

56. Insert Interval

Intervals
Medium

57. Merge Intervals

Intervals
Medium

58. Non Overlapping Intervals

Intervals
Medium

59. Meeting Rooms

Intervals
Easy

60. Meeting Rooms II

Intervals
Medium

61. Rotate Image

Math & Geometry
Medium

62. Spiral Matrix

Math & Geometry
Medium

63. Set Matrix Zeroes

Math & Geometry
Medium

64. Number of 1 Bits

Bit Manipulation
Easy

65. Counting Bits

Bit Manipulation
Easy

66. Reverse Bits

Bit Manipulation
Easy

67. Missing Number

Bit Manipulation
Easy

68. Sum of Two Integers

Bit Manipulation
Medium