DS & Algorithms

Master data structures, algorithms, and the exact coding patterns that top tech companies test for. This isn't theory for theory's sake — every concept here maps directly to what interviewers evaluate.

16Concepts

23Patterns

150Problems

Your Learning Path

Four sections, one clear path. Master the concepts, learn the patterns, drill the essentials, then push beyond.

Concepts

The foundational knowledge — data structures and algorithms explained with visual diagrams, complexity analysis, and real implementations.

Explore

Patterns

The secret sauce that separates candidates who solve 500 problems randomly from those who solve 50 strategically. Reusable templates for every pattern.

Explore

Essential 75

The 75 most frequently asked coding problems at top tech companies. Each with multiple approaches, key insights, and solutions in Python & JavaScript.

Explore

Beyond 75

The next 75 most important problems after the Essential 75. Advanced patterns, tougher variations, and the problems that separate good from great.

Explore

Mock Practice

150

Simulate a real coding interview with a 45-minute timed session, 2 random problems, interviewer-style chat, and ChatGPT-powered code evaluation.

DS & Algorithms

Your Learning Path

Concepts

Patterns

Essential 75

Beyond 75

Mock Practice

Featured Concepts

Arrays & Strings

Linked Lists

Stacks & Queues

Hash Maps & Hash Sets

Binary Trees & BST

Heaps / Priority Queues

Graphs

Tries

Top Patterns

Two Pointers

Sliding Window

Linked List Patterns

String Manipulation

Prefix Sum

Hashing & Sets

Binary Search

Kadane's Algorithm