Interactive CS, visualized
See how algorithms think.
The ultimate playground for data structures, algorithms, and system design. Don't grind problems — watch concepts come alive through animation, then build real intuition.
- 32+
- Topics
- 32
- Live visualizers
- 3
- Pillars
bubble_sort.run()live
O(n log n)
visited[ ]
Array
Linked List
Doubly Linked List
Stack
Queue
Hash Table
Binary Search Tree
Heap / Priority Queue
Trie (Prefix Tree)
Graph
Union-Find (DSU)
Bubble Sort
Selection Sort
Insertion Sort
Merge Sort
Quick Sort
Linear Search
Binary Search
Breadth-First Search
Depth-First Search
Dijkstra's Shortest Path
Two Pointers
Sliding Window
Recursion & The Call Stack
Backtracking
Dynamic Programming
Load Balancing
Caching
Database Sharding
Consistent Hashing
Message Queues
Rate Limiting
Array
Linked List
Doubly Linked List
Stack
Queue
Hash Table
Binary Search Tree
Heap / Priority Queue
Trie (Prefix Tree)
Graph
Union-Find (DSU)
Bubble Sort
Selection Sort
Insertion Sort
Merge Sort
Quick Sort
Linear Search
Binary Search
Breadth-First Search
Depth-First Search
Dijkstra's Shortest Path
Two Pointers
Sliding Window
Recursion & The Call Stack
Backtracking
Dynamic Programming
Load Balancing
Caching
Database Sharding
Consistent Hashing
Message Queues
Rate Limiting
Three pillars
Everything an engineer needs to truly understand.
singly_linked_listhead → … → null
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7●
13●
4●
21●
9●
node.next points to the next node in memory — inserting is just rewiring a pointer.
Why it works
Memorizing fades.
Seeing it move sticks.
A linked list isn't a definition to recite — it's pointers being rewired. When you watch a node splice into place, the mechanics become obvious and unforgettable.
Watch
Every concept animated step by step.
Play
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Grasp Big-O
Feel why complexity matters.
Your next interview starts with understanding.
Pick a data structure, hit play, and watch it click. No login, no friction — just learning.
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