Code Challenges

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200+ curated coding challenges covering DSA, algorithms, and real interview patterns. Solve in JavaScript, Python, Java, and more. Run tests, get AI hints, and track mastery.

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JavaScriptTypeScriptPythonJavaC++GoSQL

Easy80+

ArraysStringsHashingTwo Pointers

Medium100+

TreesGraphsDPSliding Window

Hard40+

Advanced DPSegment TreesNetwork Flow

Sample Challenges

Two Sum

Arrays & Hashing · JavaScript

easy

Longest Substring Without Repeating Chars

Sliding Window · Python

medium

Merge K Sorted Lists

Linked Lists · Java

hard

Valid Parentheses

Stack · TypeScript

easy

Binary Tree Level Order Traversal

BFS / Trees · Python

medium

Trapping Rain Water

Two Pointers · JavaScript

hard

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