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.
- 73problems
- 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 |
|---|---|---|---|
| 1 | Min Cost Climbing Stairs Dynamic Programming | 65.21% | Easy |
| 2 | Path Existence Between Two Nodes Graph | 80.12% | Easy |
| 3 | BFS Traversal Graph | 83.12% | Easy |
| 4 | DFS Traversal Graph · DFS · Traversal | 85.64% | Easy |
| 5 | Remove Duplicates From A String String · Stack | 61.68% | Easy |
| 6 | Remove Consecutive Duplicates Recursion | 60.00% | Easy |
| 7 | Find Element in a Sorted Array Binary Search | 80.00% | Easy |
| 8 | Binary Tree Post Order Traversal Tree · Recursion · Traversal | 79.59% | Easy |
| 9 | Find Maximum in BST Tree · Traversal · Binary Tree | 85.54% | Easy |
| 10 | Find Minimum in BST Tree · Traversal · Binary Tree | 85.18% | Easy |
| 11 | Count Non-Leaf Nodes In Binary Tree Tree · Traversal · Binary Tree | 60.48% | Easy |
| 12 | Search / Insert into BST Tree · Traversal · Binary Tree | 89.54% | Easy |
| 13 | Binary Tree Level Order Traversal Tree · Recursion · Traversal | 79.68% | Easy |
| 14 | Binary Tree Inorder Traversal Recursion · Trees · Traversal | 75.68% | Easy |
| 15 | Binary Tree Preorder Traversal Tree · Recursion · Binary Tree | 79.85% | Easy |
| 16 | Reverse A Linked List Linked List | 79.00% | Easy |
| 17 | Length of Linked List Linked List | 76.00% | Easy |
| 18 | Find Middle of Linked List Linked List | 87.00% | Easy |
| 19 | Peak Element In Rotated Array Recursion | 88.00% | Easy |
| 20 | Find Rotation Count Binary Search | 75.00% | Easy |
| 21 | Search in Rotated Array II Binary Search | 79.00% | Easy |
| 22 | Upper Bound Binary Search | 80.00% | Easy |
| 23 | Check if Element Exists Binary Search | 87.00% | Easy |
| 24 | Binary Search (Iterative) Binary Search | 79.00% | Easy |
| 25 | Partition Equal Subset Recursion | 77.00% | Easy |
| 26 | Factorial of N Recursion | 60.00% | Easy |
| 27 | Replace pi to 3.14 Recursion | 75.00% | Easy |
| 28 | Remove All Occurrence of A Character Recursion | 75.00% | Easy |
| 29 | Count Characters Recursion | 85.00% | Easy |
| 30 | Check Palindrome Recursion | 90.00% | Easy |
| 31 | Reverse A String Recursion | 48.00% | Easy |
| 32 | Product of All Array Elements Recursion | 80.00% | Easy |
| 33 | Sum of Array Elements Recursion | 58.00% | Easy |
| 34 | Reverse An Array Recursion | 85.00% | Easy |
| 35 | All Occurrence Of An Element Recursion | 59.00% | Easy |
| 36 | Last Occurrence Of An Element Recursion | 65.00% | Easy |
| 37 | First Occurrence Of An Element In An Array Recursion | 75.00% | Easy |
| 38 | Smallest window of 0, 1 and 2 String | 50.00% | Easy |
| 39 | Find Maximum / Minimum in Array Recursion | 75.00% | Easy |
| 40 | Print Array Elements Recursion | 50.00% | Easy |
| 41 | Fibonacci Series Recursion | 85.00% | Easy |
| 42 | Power of (a^b) Recursion | 85.00% | Easy |
| 43 | Roman Number to Integer String | 43.21% | Easy |
| 44 | Missing And Repeating Array | 24.83% | Easy |
| 45 | Longest Common Prefix Array · String | 44.20% | Easy |
| 46 | 2Sum - Pair With Given Sum Array · Hashing · Hashmap | 30.61% | Easy |
| 47 | Print Numbers from 1 to N Recursion | 75.00% | Easy |
| 48 | Print Number From N to 1 Recursion | 80.00% | Easy |
| 49 | Sum Of First N Natural Numbers Recursion | 60.00% | Easy |
| 50 | Largest subarray of 0's and 1's Data Structures Basics | 50.00% | Easy |
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.
