Complete DSA Learning System

Master DSA.
Crack LeetCode Hard.

A structured 16-week journey from absolute zero to confidently solving LeetCode Hard problems — with visual explanations, pattern recognition, and logic-building drills.

Start Learning → View Roadmap

Two Pointers · O(n) while (left < right) { int sum = arr[left] + arr[right]; if (sum == target) return {left, right}; sum < target ? left++ : right--; }

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Learning Phases

Weeks Curriculum

Practice Problems

Core Patterns

Hard Walkthroughs

Why This Matters

Why You Should Master DSA

DSA isn't just for interviews — it's how you think like a real engineer

🎯

Crack Any Tech Interview

FAANG, startups, and top-tier companies all test DSA. Master 20 patterns and solve 80% of problems within 2 minutes of reading them.

🧠

Think Like an Engineer

DSA trains your brain to break complex problems into smaller parts, choose optimal approaches, and write code that scales from 100 to 100 million inputs.

⚡

Write Faster Code

Know when to use a hash map vs binary search vs sliding window. The difference between O(n²) and O(n) can mean 10× faster real-world performance.

📈

Level Up Your Career

DSA skills directly correlate with higher compensation. Senior engineers who understand algorithms make better architecture decisions every day.

🏗️

Build Better Systems

From database indexing (B-trees) to GPS routing (Dijkstra) to caching (LRU) — algorithms power every system you use and build.

🔓

Unlock Competitive Programming

Participate in Codeforces, LeetCode contests, and hackathons. Competitive programming builds speed, accuracy, and deep algorithmic intuition.

Methodology

The 5-Step Learning System

Every topic follows the same proven methodology for deep understanding

🧠

Concept First

Understand the WHY before the code. Real-world analogies and intuition building.

🎨

Visual Diagrams

Step-by-step animated diagrams for every data structure and algorithm.

💻

Code It

Pseudocode → C++ implementation with line-by-line explanation.

🎯

Pattern Match

Learn to recognize which pattern applies from problem description alone.

⚡

Graded Practice

Easy → Medium → Hard with full solutions and detailed dry runs.

Learning Path

5 Phases to Mastery

Complete each phase sequentially — every phase builds on the last

Phase 1 · Week 1

🧩

Foundation & Mindset

Big-O complexity, problem-solving strategy, pseudocode practice, and the mindset shift from coding to thinking.

Big-O Complexity Logic Building 10 Drills

Phase 2 · Weeks 2–5

🏗️

Data Structures

Arrays, Linked Lists, Stacks, Queues, Trees, Graphs, Heaps, and Hashing — implemented from scratch with visuals.

Arrays Trees Graphs Heaps 56 Problems

Phase 3 · Weeks 6–9

⚙️

Core Algorithms

Sorting, Searching, Recursion, Dynamic Programming, Greedy, Backtracking, and Divide & Conquer.

Sorting DP Greedy Backtracking 56 Problems

Phase 4 · Weeks 10–12

🚀

Advanced Techniques

Two Pointers, Sliding Window, Monotonic Stack, Tries, Bit Manipulation, and Segment Trees.

Two Pointers Sliding Window Tries Bit Ops 30 Problems

Phase 5 · Weeks 13–16

🏆

LeetCode Hard Mastery

20 core patterns, 100 Hard problem walkthroughs, pattern recognition training, and mock contests.

20 Patterns 100 Hards Mock Contest Pattern Recognition

Week by Week

Full 16-Week Curriculum

Every topic, every week — sequenced for maximum retention. Click any chip to go straight to that topic.

Week 1 Phase 1 — Foundation & Mindset

Foundation Hub

Weeks 2–5 Phase 2 — Data Structures

Arrays Linked Lists Stacks & Queues Trees Graphs Heaps Hashing

Weeks 6–9 Phase 3 — Core Algorithms

Sorting Searching Recursion Dynamic Programming Greedy Backtracking Divide & Conquer

Weeks 10–12 Phase 4 — Advanced Techniques

Two Pointers Sliding Window Monotonic Stack Tries Bit Manipulation Segment Trees

Weeks 13–16 Phase 5 — LeetCode Hard Mastery

20 Patterns Cheatsheet Hard Walkthroughs Mock Contest Problem Bank · 615

Phase 5 Preview

20 Core Patterns for Hard Problems

Hover a pill to preview the "recognize it when…" cue and example problems.

Hover a pattern pill to preview

Each pattern maps a class of problems to a known template — recognize the pattern, code follows automatically.

Your Journey

Step-by-Step Roadmap

16 weeks from scratch to LeetCode Hard confidence

Week 1 — Phase 1

Build Your Thinking Foundation

Before writing a single line of code, learn HOW to read problems, analyze complexity, and break any problem into sub-problems.

Big-O NotationSpace ComplexityPseudocode10 Logic Drills

Weeks 2–5 — Phase 2

Master Every Data Structure

Learn how arrays, linked lists, trees, graphs, heaps, and hash maps work internally — with animated visuals and 56 practice problems.

7 DS topics56 problemsAnimations

Weeks 6–9 — Phase 3

Conquer Core Algorithms

From sorting and recursion to Dynamic Programming and Greedy — the techniques that power 90% of all problems.

7 algo topics56 problemsFirst Hard problems

Weeks 10–12 — Phase 4

Learn Advanced Techniques

The tricks that appear in Hard problems: Monotonic Stack, Tries, Segment Trees, Bit Manipulation. Rare but essential.

6 advanced topics30 problemsMedium→Hard shift

Weeks 13–16 — Phase 5

Crack LeetCode Hard

Pattern recognition training, 100 Hard walkthroughs, and weekly mock contests. You'll know which pattern to use within 2 minutes.

20 patterns100 HardsMock contestsPattern recognition

Your Progress

Phase Completion

Progress is saved automatically in your browser

Phase 1 — Foundation

Phase 2 — Data Structures

Phase 3 — Algorithms

Phase 4 — Advanced

Phase 5 — LeetCode Hard

Master DSA. Crack LeetCode Hard.