{}Free Course · Beginner → Advanced

The Complete Data Structures Course

A comprehensive, visual journey through data structures and algorithms — from arrays and linked lists to balanced trees, hashing, and graphs. Every structure and algorithm is brought to life with interactive, animated visualizations, and every code example is available in Python, Java, C++, and pseudocode.

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31
Modules
7
Phases
19h+
Of reading

Phase 1 · Foundations

What data structures are, Big-O complexity, and recursion.

Module 1Available

Introduction to Data Structures & Algorithms

What data structures and algorithms really are, the difference between an abstract data type and its implementation, and how to choose the right structure.

~30 min6 topicsStart
Module 2Available

Measuring Efficiency: Big-O & Complexity

Reason about how fast and how memory-hungry an algorithm is, independent of the machine it runs on.

~38 min6 topicsStart
Module 3Available

Recursion & the Call Stack

The problem-solving technique behind trees, graphs, and divide-and-conquer — and exactly how the call stack runs it.

~36 min6 topicsStart

Phase 2 · Linear Structures

Arrays, linked lists, stacks, queues, and deques.

Module 4Available

Arrays & Dynamic Arrays

The most fundamental structure: contiguous memory, O(1) indexing, and how dynamic arrays grow behind the scenes.

~38 min6 topicsStart
Module 5Available

Singly Linked Lists

Nodes joined by pointers — insert and delete in O(1), with no shifting, at the cost of no random access.

~38 min6 topicsStart
Module 6Available

Doubly & Circular Linked Lists

Add a backward pointer for two-way traversal, and join the ends to form circular lists.

~32 min6 topicsStart
Module 7Available

Stacks (LIFO)

Last-in, first-out — the structure behind undo, the call stack, and expression evaluation.

~32 min6 topicsStart
Module 8Available

Queues, Deques & Circular Buffers

First-in, first-out and its cousins — the ring buffer and the double-ended queue.

~34 min6 topicsStart

Phase 3 · Searching & Sorting

Binary search and the classic sorting algorithms, animated.

Module 9Available

Searching: Linear & Binary Search

Find an element fast — and see why a sorted array unlocks O(log n) binary search.

~32 min6 topicsStart
Module 10Available

Elementary Sorts

Bubble, selection, and insertion sort — simple, O(n²), and the perfect way to learn to compare algorithms.

~38 min6 topicsStart
Module 11Available

Merge Sort

Divide, conquer, and merge your way to a stable O(n log n) sort.

~36 min6 topicsStart
Module 12Available

Quick Sort

The fast in-place sorter that powers many standard libraries — and its worst-case trap.

~38 min6 topicsStart
Module 13Available

Heap Sort & Linear-Time Sorts

Sort with a heap, then break the O(n log n) barrier with counting, radix, and bucket sort.

~36 min6 topicsStart

Phase 4 · Hashing

Hash tables, hash functions, and collision resolution.

Module 14Available

Hash Tables & Hash Functions

Average O(1) lookup by turning keys into array indexes with a hash function.

~36 min6 topicsStart
Module 15Available

Collisions & Load Factor

Two keys, one bucket — how chaining and open addressing keep hash tables fast, and when they rehash.

~34 min6 topicsStart

Phase 5 · Trees

Binary trees, BSTs, balanced trees, heaps, tries, and B-trees.

Module 16Available

Trees & Traversals

Hierarchical data, binary trees, and the four ways to visit every node.

~38 min6 topicsStart
Module 17Available

Binary Search Trees

Keep data sorted and searchable in O(log n) — insert, search, and the tricky three-case delete.

~42 min6 topicsStart
Module 18Available

AVL Trees

The first self-balancing BST — heights stay in check with four rotations.

~40 min6 topicsStart
Module 19Available

Red-Black Trees

The balanced tree inside many standard libraries — balance through coloring and rotation.

~40 min6 topicsStart
Module 20Available

Heaps & Priority Queues

A complete binary tree in an array that always gives you the min or max in O(1).

~38 min6 topicsStart
Module 21Available

Tries (Prefix Trees)

Store strings by their characters for lightning-fast prefix search and autocomplete.

~34 min6 topicsStart
Module 22Available

B-Trees & B+ Trees

Multi-way balanced trees built for disk — the structure behind databases and file systems.

~38 min6 topicsStart

Phase 6 · Graphs

Representations, traversal, shortest paths, MST, and union-find.

Module 23Available

Graph Fundamentals & Representations

Model networks of anything — and choose between an adjacency matrix and an adjacency list.

~38 min6 topicsStart
Module 24Available

Graph Traversal: BFS & DFS

Visit every vertex systematically — with a queue (BFS) or a stack/recursion (DFS).

~40 min6 topicsStart
Module 25Available

Topological Sort & Cycle Detection

Order tasks with dependencies, and detect the cycles that make ordering impossible.

~34 min6 topicsStart
Module 26Available

Shortest Paths I: Dijkstra & Bellman-Ford

Find the cheapest route through a weighted graph — with and without negative edges.

~42 min6 topicsStart
Module 27Available

Shortest Paths II & A*

All-pairs shortest paths and the heuristic search that powers game and map pathfinding.

~38 min6 topicsStart
Module 28Available

Minimum Spanning Trees: Kruskal & Prim

Connect every vertex at the lowest total cost with two classic greedy algorithms.

~38 min6 topicsStart
Module 29Available

Union-Find (Disjoint Set)

Track connectivity almost in constant time with union by rank and path compression.

~34 min6 topicsStart

Phase 7 · Mastery

Amortized analysis, advanced structures, and choosing the right one.

Module 30Available

Amortized Analysis & Advanced Structures

The averaging argument behind dynamic arrays, plus a tour of Fenwick trees, segment trees, skip lists, and the LRU cache.

~40 min6 topicsStart
Module 31Available

Choosing the Right Structure

Bring it all together: a decision framework, the master Big-O cheat sheet, and common interview patterns.

~32 min6 topicsStart