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Master Algorithms & Ace the Interview

Learn algorithms through interactive visualizations, then prove your skills with 70+ coding challenges. Earn knowledge badges, track your progress, and prepare for coding interviews — all in your browser.

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Algorithms

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From visual explanations to hands-on coding practice

Interactive Visualizations

Watch algorithms come alive with step-by-step animations. Pause, rewind, and step through each operation at your own pace.

Code in JS & Python

Every algorithm includes clean, runnable implementations in both JavaScript and Python with syntax highlighting.

Built-in Code Editor

Write and test solutions in a full-featured editor with Vim mode, multiple themes, and instant test feedback — no setup needed.

70+ Coding Challenges

Practice with LeetCode-style problems rated by difficulty. Each problem includes test cases, examples, and constraint checks.

Knowledge & Badges

Earn knowledge by mastering each algorithm topic. Unlock achievement badges like "Master of the Forest" and "The Oracle".

Run in Browser

Execute code instantly using sandboxed Web Workers. Test your solutions against real test cases — all client-side, zero latency.

Practice Makes Perfect

Solve 70+ algorithm challenges in a built-in code editor. Run tests, earn knowledge, and collect badges as you progress.

1function twoSum(nums, target) {

2const map = new Map();

3for (let i = 0; i < nums.length; i++) {

4const complement = target - nums[i];

5if (map.has(complement))

6return [map.get(complement), i];

7map.set(nums[i], i);

4/4 passedAll tests passed

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Explore Topics

From sorting basics to advanced graph algorithms

Arrays & Strings

4 topics

Array Operations String Manipulation Matrix Traversal Two-Dimensional Arrays

Sorting

8 topics

Bubble Sort Quick Sort Merge Sort Heap Sort Insertion Sort Selection Sort Counting Sort Radix Sort

Searching

4 topics

Linear Search Binary Search Depth-First Search Breadth-First Search

Trees

5 topics

Binary Search Tree AVL Tree Trie Segment Tree Binary Heap

Graphs

7 topics

Dijkstra's Algorithm Bellman-Ford Floyd-Warshall Kruskal's MST Prim's MST Topological Sort Connected Components

Dynamic Programming

7 topics

Fibonacci 0/1 Knapsack Longest Common Subsequence Coin Change Edit Distance House Robber Longest Increasing Subsequence

Linked Lists

3 topics

Singly Linked List Doubly Linked List Circular Linked List

Stacks & Queues

4 topics

Stack Queue Deque Priority Queue

Hash Tables

2 topics

Hash Table (Chaining)Hash Table (Open Addressing)

Advanced

3 topics

Union-Find Bloom Filter Skip List

Patterns

9 topics

Two Pointers Sliding Window Prefix Sum Backtracking Divide and Conquer Greedy Algorithms Monotonic Stack Interval Problems Recursion

Math & Number Theory

4 topics

GCD and LCM Modular Arithmetic Combinatorics Sieve of Eratosthenes

Coding Principles

13 topics

Single Responsibility Open/Closed Principle Liskov Substitution Interface Segregation Dependency Inversion DRY KISS YAGNI Composition over Inheritance Law of Demeter Separation of Concerns Fail Fast Convention over Configuration

OOP

8 topics

Classes & Objects Encapsulation Inheritance Polymorphism Abstraction Method Overriding Interfaces & Abstract Classes Association & Composition

Functional Programming

8 topics

Pure Functions Immutability Higher-Order Functions Closures Currying Function Composition Map, Filter, Reduce Recursion in FP

Process & Thread

7 topics

What is a Process What is a Thread Process vs Thread Process Lifecycle Thread Lifecycle Inter-Process Communication Context Switching

Concurrency

10 topics

Mutex & Locks Semaphores Deadlock Race Conditions Producer-Consumer Problem Readers-Writers Problem Thread Pool Async/Await Pattern Event Loop Concurrency vs Parallelism

Bitwise Operations

8 topics

AND, OR, XOR, NOT Left Shift & Right Shift Bit Masking Check/Set/Clear/Toggle Bit Count Set Bits Power of Two Check Swap Without Temp Bit Manipulation Tricks

Networking

7 topics

OSI Model TCP vs UDP HTTP/HTTPS DNS REST API WebSocket TLS/SSL Handshake

Relational Database

7 topics

Tables, Rows & Columns Primary & Foreign Keys SQL Joins Indexing Normalization ACID Properties Transactions

System Design

5 topics

URL Shortener Rate Limiter Chat System News Feed Distributed Cache

Master Algorithms & Ace the Interview

Learn by Doing

Interactive Visualizations

Code in JS & Python

Built-in Code Editor

70+ Coding Challenges

Knowledge & Badges

Run in Browser

Practice Makes Perfect

Difficulty Levels

Achievement Badges

Explore Topics

Arrays & Strings

Sorting

Searching

Trees

Graphs

Dynamic Programming

Linked Lists

Stacks & Queues

Hash Tables

Advanced

Patterns

Math & Number Theory

Design Patterns

Coding Principles

OOP

Functional Programming

Process & Thread

Concurrency

Bitwise Operations

Networking

Relational Database

System Design