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.
- 74problems
- 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 | Diamond Pattern Data Structures Basics · String | 94.13% | Basic |
| 2 | Find the Nth Prime Number Data Structures Basics · Searching Algorithm · Basics | 84.00% | Basic |
| 3 | Find All Primes in a Range Data Structures Basics · Searching Algorithm · Basics | 98.24% | Basic |
| 4 | Find the Longest Consecutive Sequence of the Same Digit Data Structures Basics · Array · String | 84.75% | Basic |
| 5 | Check Whether Digits Alternate in Parity Data Structures Basics · String · Searching Algorithms | 78.04% | Basic |
| 6 | Check Whether Digits Are Strictly Decreasing Data Structures Basics · String · Searching Algorithms | 87.15% | Basic |
| 7 | Swap the First and Last Digits of a Number Data Structures Basics · String | 78.12% | Basic |
| 8 | Remove All Occurrences of a Digit Data Structures Basics · Array · String | 78.62% | Basic |
| 9 | Check Whether All Digits Are Distinct Data Structures Basics · String · Searching Algorithms | 79.18% | Basic |
| 10 | Rotate Digits of a Number to the Right Data Structures Basics · String · Basics | 86.67% | Basic |
| 11 | DFS Traversal Graph · DFS · Traversal | 85.64% | Easy |
| 12 | Remove Duplicates From A String String · Stack | 61.68% | Easy |
| 13 | Binary Tree Cameras Tree · Traversal · Binary Tree | 55.21% | Hard |
| 14 | Boundary Traversal Tree · Traversal · Binary Tree | 45.21% | Hard |
| 15 | Compare Leaf Traversal Tree · Traversal · Binary Tree | 77.95% | Medium |
| 16 | Binary Tree Post Order Traversal Tree · Recursion · Traversal | 79.59% | Easy |
| 17 | Inorder Successor in BST Tree · Traversal · Binary Tree | 60.12% | Medium |
| 18 | Kth Largest Element in BST Tree · Traversal · Binary Tree | 70.53% | Medium |
| 19 | Construct Tree from Inorder + Postorder Tree · Traversal · Binary Tree | 65.12% | Medium |
| 20 | Top View of Binary Tree Tree · Traversal · Binary Tree | 60.21% | Medium |
| 21 | Convert Sorted Array to BST Tree · Traversal · Binary Tree | 74.56% | Medium |
| 22 | Find Maximum in BST Tree · Traversal · Binary Tree | 85.54% | Easy |
| 23 | Find Minimum in BST Tree · Traversal · Binary Tree | 85.18% | Easy |
| 24 | Find Distance Between Two Nodes Tree · Traversal · Binary Tree | 62.45% | Medium |
| 25 | All Paths With Given Sum Tree · Traversal · Binary Tree | 74.23% | Medium |
| 26 | Maximum Root to Leaf Path Sum Tree · Traversal · Binary Tree | 72.15% | Medium |
| 27 | Count Non-Leaf Nodes In Binary Tree Tree · Traversal · Binary Tree | 60.48% | Easy |
| 28 | Minimum Depth of Binary Tree Tree · Traversal · Binary Tree | 60.25% | Medium |
| 29 | Construct Tree from Inorder + Preorder Tree · Traversal · Binary Tree | 70.00% | Medium |
| 30 | Right View of Binary Tree Tree · Traversal · Binary Tree | 74.36% | Medium |
| 31 | Lowest Common Ancestor in BST Tree · Traversal · Binary Tree | 70.50% | Medium |
| 32 | Kth Smallest Element in BST Tree · Traversal · Binary Tree | 76.77% | Medium |
| 33 | Maximum Path Sum in Binary Tree Tree · Traversal · Binary Tree | 58.59% | Hard |
| 34 | Delete Node In BST Tree · Traversal · Binary Tree | 65.20% | Medium |
| 35 | Validate BST Tree · Traversal · Binary Tree | 45.23% | Medium |
| 36 | Search / Insert into BST Tree · Traversal · Binary Tree | 89.54% | Easy |
| 37 | Find Nodes at Distance K from Given Node Tree · Traversal · Binary Tree | 65.95% | Hard |
| 38 | Lowest Common Ancestor of Binary Tree Tree · Traversal · Binary Tree | 78.59% | Medium |
| 39 | Print All Root To Leaf Paths Tree · Traversal · Binary Tree | 68.59% | Hard |
| 40 | Root To Leaf Path Sum Tree · Traversal · Binary Tree | 78.56% | Medium |
| 41 | Diameter of Binary Tree Tree · Traversal · Binary Tree | 73.45% | Medium |
| 42 | Check Binary Tree Is Balanced Tree · Traversal · Binary Tree | 78.95% | Medium |
| 43 | Check if Tree is Symmetric Tree · Traversal · Binary Tree | 74.98% | Medium |
| 44 | Check if Two Trees are Identical Tree · Traversal · Binary Tree | 76.59% | Medium |
| 45 | Count Leaf Nodes In Binary Tree Tree · Traversal · Binary Tree | 74.59% | Medium |
| 46 | Count Total Nodes in Binary Tree Tree · Traversal · Binary Tree | 75.68% | Medium |
| 47 | Height / Max Depth of Binary Tree Tree · Traversal · Binary Tree | 75.36% | Medium |
| 48 | Binary Tree Zigzag Level Order Traversal Tree · Recursion · Traversal | 71.48% | Medium |
| 49 | Binary Tree Level Order Traversal Tree · Recursion · Traversal | 79.68% | Easy |
| 50 | Binary Tree Inorder Traversal Recursion · Trees · Traversal | 75.68% | 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.
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