Free forever — 9 topics — no signup required

Master algorithms by topic.

A systematic learning path from strings to graphs.
Pick a topic. Read the theory. Solve the problems.

Start Learning→How it works

0Core Topics

0+Problems

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Process

How it works

Three steps to go from zero to interview-ready on any topic.

Step 01

Choose your starting point

Select any of the 9 core algorithm topics. Beginners start with String or Array. Advanced learners jump to Graph or DP.

Step 02

Theory with real code

Read focused guides that explain the core pattern, not every edge case. Every example includes time and space complexity.

Step 03

Solve, then understand

Curated problems sorted Easy → Hard. Each links to a full solution walkthrough so you know why, not just what.

Learning Path

9 topics. One clear path.

Each topic builds on the last. Start with strings, finish interview-ready.

🔤

String

Pattern matching, parsing, and string algorithms

Two pointers, sliding window, and array manipulation

Two PointersPrefix Sum

→

🔗

Linked List

Singly and doubly linked lists, pointers

LIFO operations and stack-based solutions

FIFO operations and BFS foundations

Binary trees, BST, traversal, and recursion

DFS, BFS, shortest path, and graph algorithms

Memoization, tabulation, and optimization

MemoizationTabulation

→

🔀

Backtracking

Combinations, permutations, and constraint satisfaction

CombinationsPruning

→

Free forever

Ready to get interview-ready?

Start with the fundamentals or jump straight to the topic you need most. No account required.

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