Encounter with Algorithms Complexity analysis Array and linked list Stack and queue Hash table Tree Heap Graph Searching Sorting Divide and conquer Backtracking Dynamic programming Greedy

Data structures and algorithms crash course with animated illustrations and off-the-shelf code

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500 animated illustrations, 14 programming languages, and 3000 community Q&As to help you quickly get started with data structures and algorithms

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### Endorsements

“An easy-to-understand book on data structures and algorithms, which guides readers to learn by minds-on and hands-on. Strongly recommended for algorithm beginners!”

—— Junhui Deng, Professor, Department of computer science and technology, Tsinghua University

“If I had 'Hello Algo' when I was learning data structures and algorithms, it would have been 10 times easier!”

—— Mu Li, Senior principal scientist, Amazon

### Animated illustrations

It's crafted for ease of understanding, ensuring a smooth learning journey.

"A picture is worth a thousand words."

### Off-the-shelf code

Featuring multiple programming languages, all runnable with a single click.

"Talk is cheap. Show me the code."

### Learning together

Welcome discussions and questions with open arms.

"Learning by teaching."

### Author

Yudong Jin（@krahets）

### Code reviewers

codingonion
Zig, Rust
curtishd
Kotlin
Gonglja
C, C++
gvenusleo
Dart
hpstory
C#
justin-tse
JS, TS
krahets
Python, Java
night-cruise
Rust
nuomi1
Swift
Reanon
Go, C

### Contributors

This book has been enhanced through the collaborative efforts of more than 100 contributors. Thanks for their invaluable time and input!