The full library

Every algorithm, one 3D canvas.

132 problems across arrays, sorting, linked lists, trees, stacks, queues and hashing — each with a live spatial visualization.

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Bubble Sort

Insertion Sort

Quick Sort

Sorting O(n log n)

Selection Sort

Find Smallest Number

Find Largest Number

Binary Search

Two Pointers (Two Sum)

Sliding Window (Max Sum)

Kadane's Algorithm (Max Subarray)

Find Second Largest Number

Find Second Smallest Number

Find Third Largest Number

Find Third Smallest Number

Sum of All Elements

Average of All Elements

Count Even and Odd Elements

Count Positive, Negative & Zero

Reverse Array (In-Place)

Frequency of Each Element

Find All Duplicate Elements

Remove Duplicate Elements

Find Missing Number (1 to n)

Common Elements in Array

Elements in First Not Second

Maximum Difference in Array

Minimum Difference in Array

Array O(n log n)

Move All Zeroes to End

Two Largest Elements (Without Sorting)

Two Smallest Elements (Without Sorting)

Top K Largest Elements

Array O(n log k)

Top K Smallest Elements

Array O(n log k)

Single Number (Unique in Duplicates)

Majority Element (> n/2 Times)

Elements Appearing > n/3 Times

Pair with Given Target Sum

All Pairs with Target Sum

Triplet With Target Sum (3Sum)

Max Sum Contiguous Subarray

Min Sum Contiguous Subarray

Longest Increasing Contiguous Subarray

Longest Decreasing Contiguous Subarray

Longest Consecutive Sequence

Intersection of Two Arrays

Union of Two Arrays

Product of Array Except Self

Maximum Product of Two Elements

Maximum Product Subarray

Subarray With Given Sum

All Subarrays With Given Sum

Longest Subarray with Sum 0

Longest Subarray Equal 0s & 1s

Maximum Sum Circular Subarray

Smallest Positive Missing Number

Duplicate Number (1 to n)

Two Repeating Elements

First Missing Positive Integer

Best Time to Buy & Sell Stock I

Best Time to Buy & Sell Stock II

Number of Inversions in Array

Array O(n log n)

Next Greater Element

Previous Greater Element

Next Smaller Element

Previous Smaller Element

Sliding Window Maximum (Size K)

Sliding Window Minimum (Size K)

Longest Subarray with at most K Distinct

Longest Subarray Without Repeating Elements

1. Traversal of Linked List

Linked List O(n)

2. Insert at Beginning

Linked List O(1)

3. Insert at End

Linked List O(n)

4. Insert at Specific Position

Linked List O(n)

5. Delete from Beginning

Linked List O(1)

6. Delete from End

Linked List O(n)

7. Delete by Value

Linked List O(n)

8. Search an Element

Linked List O(n)

9. Find Length of Linked List

Linked List O(n)

10. Reverse a Linked List ⭐

Linked List O(n)

11. Find Middle Node ⭐

Linked List O(n)

12. Detect Cycle / Loop ⭐

Linked List O(n)

13. Find Starting Node of Cycle ⭐

Linked List O(n)

14. Remove Cycle

Linked List O(n)

15. Find Nth Node from End ⭐

Linked List O(n)

16. Intersection Point of Two Lists ⭐

Linked List O(n + m)

17. Check Palindrome Linked List ⭐

Linked List O(n)

18. Merge Two Sorted Linked Lists ⭐

Linked List O(n + m)

19. Sort a Linked List (Merge Sort) ⭐

Linked List O(n log n)

20. Remove Duplicates (Sorted List)

Linked List O(n)

21. Delete Node Without Head Pointer

Linked List O(1)

22. Find Length of Cycle

Linked List O(n)

23. Split List into Two Halves

Linked List O(n)

24. Rotate Linked List by K Positions

Linked List O(n)

Two Sum (Hash Map)

Frequency Counter (Hash Map)

First Unique Element (Hash Map)

Longest Consecutive Sequence (Hash Set)

Stack Operations (Push & Pop)

Valid Parentheses ()[]{}

Next Greater Element (Monotonic Stack)

Min Stack (O(1) Minimum)

Queue Operations (FIFO)

Circular Queue (Ring Buffer)

Deque (Double-Ended Queue)

Priority Queue (Min-Heap)

1. Preorder Traversal (Root → Left → Right) ⭐

Binary Trees O(n)

2. Inorder Traversal (Left → Root → Right) ⭐

Binary Trees O(n)

3. Postorder Traversal (Left → Right → Root) ⭐

Binary Trees O(n)

4. Level Order Traversal (BFS) ⭐

Binary Trees O(n)

5. Height / Depth of Binary Tree ⭐

Binary Trees O(n)

6. Count Total Nodes

Binary Trees O(n)

7. Count Leaf Nodes

Binary Trees O(n)

8. Search in Binary Tree

Binary Trees O(n)

9. Insert in BST ⭐

Binary Trees O(h)

10. Search in BST ⭐

Binary Trees O(log n)

11. Delete Node in BST ⭐

Binary Trees O(h)

12. Find Minimum & Maximum in BST

Binary Trees O(h)

13. Inorder Successor & Predecessor ⭐

Binary Trees O(h)

14. Check if Tree is a BST ⭐

Binary Trees O(n)

15. Lowest Common Ancestor (LCA) ⭐

Binary Trees O(n)

16. Check if Two Trees are Identical

Binary Trees O(n)

17. Mirror / Invert a Binary Tree ⭐

Binary Trees O(n)

18. Check Balanced Binary Tree ⭐

Binary Trees O(n)

19. Diameter of Binary Tree ⭐

Binary Trees O(n)

20. Build Tree from Preorder + Inorder ⭐

Binary Trees O(n)

21. Build Tree from Postorder + Inorder

Binary Trees O(n)

22. Left View & Right View of Tree

Binary Trees O(n)

23. Top View & Bottom View

Binary Trees O(n)

24. Boundary Traversal

Binary Trees O(n)

25. Zigzag / Spiral Level Order

Binary Trees O(n)

26. Root-to-Leaf Paths

Binary Trees O(n)

27. Maximum Path Sum ⭐

Binary Trees O(n)

28. Binary Tree to Doubly Linked List

Binary Trees O(n)

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