Think in patterns.
Solve like it’s the interview.
hand-picked DSA problems in C#, Java, Python, C++ and JavaScript. Run your code, climb the leaderboard and keep your streak alive.
- 142problems
- 12core patterns
- 5languages
- 2 Lakh+learners trained
Bubble sort
ArraysO(n²)Running
Compare neighbours, swap when out of order.
Inorder traversal
TreesDFSO(n)
Visit order:
Breadth-first search
GraphsQueueO(V+E)
Level order:
Longest common subsequence
Dynamic ProgrammingO(mn)
dp[i][j] = best length for the first i and j characters.
Browse by pattern
Master the idea once, solve the whole family.
| # | Title | Acceptance | Difficulty |
|---|---|---|---|
| 51 | Detect Cycle In Linked List Linked List | 65.00% | Medium |
| 52 | Find Start of Cycle Linked List | 57.00% | Medium |
| 53 | Nth Node From End Linked List | 69.00% | Medium |
| 54 | Kth Smallest In Multiplication Table Binary Search | 75.00% | Medium |
| 55 | Square Root of A Number Binary Search | 63.00% | Medium |
| 56 | Median Of Two Sorted Arrays Binary Search | 71.00% | Medium |
| 57 | Lower Bound Binary Search | 75.00% | Medium |
| 58 | Magnetic Force Between Two Balls Binary Search | 60.00% | Medium |
| 59 | Find Smallest Divisor Given A Threshold Binary Search | 67.00% | Medium |
| 60 | Minimise Maximum Distance To Go To Gas Station Binary Search | 64.00% | Medium |
| 61 | Capacity To Ship Packages Within D Days Binary Search | 65.00% | Medium |
| 62 | Median In Row-Wise Sorted Array Binary Search | 69.00% | Medium |
| 63 | Search in A Sorted 2D Matrix II Binary Search | 70.00% | Medium |
| 64 | Search in a 2D Matrix Recursion · Binary Search | 86.00% | Medium |
| 65 | Split Array Largest Sum Binary Search | 59.00% | Medium |
| 66 | Find Minimum In Rotated Sorted Array Recursion | 89.00% | Medium |
| 67 | Aggressive Cows Binary Search | 70.00% | Medium |
| 68 | Allocate Minimum Pages Binary Search | 62.00% | Medium |
| 69 | Minimum Speed to Arrive on Time Binary Search | 69.00% | Medium |
| 70 | Koko Eating Bananas Binary Search | 68.00% | Medium |
| 71 | Generate All Subsequence Recursion | 56.00% | Medium |
| 72 | Check if Binary Tree is Balanced Recursion | 77.00% | Medium |
| 73 | Generate All Subsets Recursion | 60.00% | Medium |
| 74 | Count Nodes in Binary Tree Recursion | 64.00% | Medium |
| 75 | Letter Combinations of Phone Number Recursion | 60.00% | Medium |
| 76 | Tiling Problem Recursion | 50.00% | Medium |
| 77 | Permutation Without Duplicates Recursion | 67.00% | Medium |
| 78 | Combination Sum II Recursion | 76.00% | Medium |
| 79 | Permutation of an Array Array · Recursion | 68.00% | Medium |
| 80 | Permutation of A String String · Recursion | 66.00% | Medium |
| 81 | Subsets with Duplicates Recursion | 74.00% | Medium |
| 82 | Count Ways To Reach Nth Stair Recursion | 60.00% | Medium |
| 83 | Friends Pairing Problem Recursion | 50.00% | Medium |
| 84 | Count Binary Strings Recursion | 60.00% | Medium |
| 85 | Fibonacci Series (Tree Recursion) Recursion | 60.00% | Medium |
| 86 | Check String Is Subsequence To Another Recursion | 75.00% | Medium |
| 87 | Convert String to Integer Recursion | 60.00% | Medium |
| 88 | Longest Palindromic Substring String | 34.80% | Medium |
| 89 | Search In Rotated Sorted Array Array · Searching Algorithms | 37.64% | Medium |
| 90 | Form Anagram Groups String · Hashing | 69.80% | Medium |
| 91 | Count Inversions Array · Sorting Algorithms | 16.93% | Medium |
| 92 | Maximize Number of 1's Array · Binary Search | 50.00% | Medium |
| 93 | Combination Sum Recursion | 75.00% | Medium |
| 94 | Length of the longest substring String | 50.00% | Medium |
| 95 | Ways to Reaching the n'th Stair Dynamic Programming | 50.00% | Medium |
| 96 | Implement Min Stack Stack | 22.59% | Medium |
| 97 | First non-repeating in a stream Queue | 31.65% | Medium |
| 98 | Binary Heap Operations Heap | 22.30% | Medium |
| 99 | Detect Loop in linked list Linked List | 43.49% | Medium |
| 100 | Palindrome Linked List Linked List | 41.48% | Medium |
Practice that builds the habit
Three steps, repeated every day.
- 1
Pick a pattern
Start from an idea such as two pointers or BFS, then move through easy, medium and hard.
- 2
Code and run
Write in your language, run on sample cases and submit against every hidden test.
- 3
Climb the board
Every solve earns points. Keep a daily streak and see where you stand this month.
Want a plan, not just problems?
The DSA bootcamp adds structured lessons, live mentorship and mock interviews on top of this practice platform.
