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 |
|---|---|---|---|
| 1 | Game with String Heap | 53.96% | Medium |
| 2 | Kth largest element Heap | 64.92% | Medium |
| 3 | Min Number of Jumps Dynamic Programming | 50.48% | Medium |
| 4 | House Robber Dynamic Programming | 51.45% | Medium |
| 5 | Odd Even Graph Check Graph | 63.45% | Medium |
| 6 | Redundant Connection Graph | 68.71% | Medium |
| 7 | Detect Cycle in Undirected Graph (DFS) Graph | 67.77% | Medium |
| 8 | Detect Cycle in Directed Graph (DFS) Graph | 67.67% | Medium |
| 9 | Level of Each Node Graph | 74.21% | Medium |
| 10 | Flood Fill Recursion | 69.00% | Medium |
| 11 | Number of Islands Recursion | 66.00% | Medium |
| 12 | Compare Leaf Traversal Tree · Traversal · Binary Tree | 77.95% | Medium |
| 13 | Inorder Successor in BST Tree · Traversal · Binary Tree | 60.12% | Medium |
| 14 | Kth Largest Element in BST Tree · Traversal · Binary Tree | 70.53% | Medium |
| 15 | Construct Tree from Inorder + Postorder Tree · Traversal · Binary Tree | 65.12% | Medium |
| 16 | Top View of Binary Tree Tree · Traversal · Binary Tree | 60.21% | Medium |
| 17 | Convert Sorted Array to BST Tree · Traversal · Binary Tree | 74.56% | Medium |
| 18 | Find Distance Between Two Nodes Tree · Traversal · Binary Tree | 62.45% | Medium |
| 19 | All Paths With Given Sum Tree · Traversal · Binary Tree | 74.23% | Medium |
| 20 | Maximum Root to Leaf Path Sum Tree · Traversal · Binary Tree | 72.15% | Medium |
| 21 | Minimum Depth of Binary Tree Tree · Traversal · Binary Tree | 60.25% | Medium |
| 22 | Construct Tree from Inorder + Preorder Tree · Traversal · Binary Tree | 70.00% | Medium |
| 23 | Right View of Binary Tree Tree · Traversal · Binary Tree | 74.36% | Medium |
| 24 | Lowest Common Ancestor in BST Tree · Traversal · Binary Tree | 70.50% | Medium |
| 25 | Kth Smallest Element in BST Tree · Traversal · Binary Tree | 76.77% | Medium |
| 26 | Delete Node In BST Tree · Traversal · Binary Tree | 65.20% | Medium |
| 27 | Validate BST Tree · Traversal · Binary Tree | 45.23% | Medium |
| 28 | Lowest Common Ancestor of Binary Tree Tree · Traversal · Binary Tree | 78.59% | Medium |
| 29 | Root To Leaf Path Sum Tree · Traversal · Binary Tree | 78.56% | Medium |
| 30 | Diameter of Binary Tree Tree · Traversal · Binary Tree | 73.45% | Medium |
| 31 | Check Binary Tree Is Balanced Tree · Traversal · Binary Tree | 78.95% | Medium |
| 32 | Check if Tree is Symmetric Tree · Traversal · Binary Tree | 74.98% | Medium |
| 33 | Check if Two Trees are Identical Tree · Traversal · Binary Tree | 76.59% | Medium |
| 34 | Count Leaf Nodes In Binary Tree Tree · Traversal · Binary Tree | 74.59% | Medium |
| 35 | Count Total Nodes in Binary Tree Tree · Traversal · Binary Tree | 75.68% | Medium |
| 36 | Height / Max Depth of Binary Tree Tree · Traversal · Binary Tree | 75.36% | Medium |
| 37 | Binary Tree Zigzag Level Order Traversal Tree · Recursion · Traversal | 71.48% | Medium |
| 38 | Intersection of Two Linked Lists Linked List | 75.00% | Medium |
| 39 | Sort A Linked List (Merge Sort) Linked List | 58.00% | Medium |
| 40 | Merge K Sorted Lists Linked List | 70.00% | Medium |
| 41 | Merge Two Sorted Linked Lists Link List | 59.00% | Medium |
| 42 | Swap Nodes in Pairs Linked List | 65.00% | Medium |
| 43 | Reverse Sublist (Between Left & Right) Linked List | 67.00% | Medium |
| 44 | Reverse Linked List in K Groups Linked List | 60.00% | Medium |
| 45 | Reverse Linked List in Pairs Linked List | 63.00% | Medium |
| 46 | Kth Smallest Pair Distance Binary Search | 65.00% | Medium |
| 47 | Find K Closest Elements Binary Search | 76.00% | Medium |
| 48 | Kth Smallest Element In A Matrix Binary Search | 70.00% | Medium |
| 49 | Remove Nth Node From End Linked List | 73.00% | Medium |
| 50 | Check if Linked List is Palindrome Linked List | 67.00% | 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.
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