Algorithms

A curated list of awesome places to learn and/or practice algorithms. Inspired by awesome-awesomeness and all the other awesome Awesome libraries.

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• Awesome Algorithms

  • Websites

  • Online Courses

  • Books

  • Github Libraries

  • Online Judges

  • Tools

Websites

Websites you should use to learn classic algorithms

• A Visual Guide to Graph Traversal Algorithms - Interactive visualisations for learning how graph traversal algorithms work

• Algomation - A didactic, animated, exposition of algorithms.

• Algorithm Visualizer - Dozens of animated algorithms (with code), and you can also create your own.

• Algorithms Visualization - A dense article on Algorithms Visualization.

• Big-O Cheat Sheet - Big-O complexities of common algorithms used in Computer Science.

• Code-Drills - Practice problems recommender (includes Codeforces, Codechef and Spoj).

• Data Structure Visualizations - Visualize the behavior of Data Structures and play with its operations.

• Geeks for Geeks - Lots and lots of well explained and implemented algorithms.

• Path Finding - A visual representation on how algorithms such as A*, IDA*, Breadth-First-Search, Best-First-Search and others describe a path between two points A and B.

• Rosetta Code - A programming chrestomathy site which aims to present implementations of many algorithms and data structures in different programming languages.

• Sorting Algorithms - Nice and simple animations of sorting algorithms. With short codes and discussions.

• Stoimen's web log - Some algorithms nicely explained.

• The Sound of Sorting - The Sound of Sorting - "Audibilization" and Visualization of Sorting Algorithms

• VisuAlgo - Visualising data structures and algorithms through animation.

• Wikipedia - Algorithms - Of course!!

• Wikipedia - Data Structures - and why not ?!!

Online Courses

Free and High Quality Courses Online

• Algorithms: Divide and Conquer, Sorting and Searching, and Randomized Algorithms - The primary topics are: asymptotic ("Big-oh") notation, sorting and searching, divide and conquer, and randomized algorithms.

• Algorithms: Graph Search, Shortest Paths, and Data Structures - The primary topics are: data structures, graph primitives, and their applications.

• Algorithms: Greedy Algorithms, Minimum Spanning Trees, and Dynamic Programming - The primary topics are: greedy algorithms and dynamic programming.

• Algorithms: Shortest Paths Revisited, NP-Complete Problems and What To Do About Them - The primary topics are: shortest paths, NP-completeness and what it means for the algorithm designer, and strategies for coping with computationally intractable problems.

• Algorithms, Part I - This course covers the essential information that every serious programmer needs to know about algorithms and data structures.Part I covers elementary data structures, sorting, and searching algorithms.

• Algorithms, Part II - Part II focuses on graph- and string-processing algorithms.

• Khan Academy Algorithms - Algorithm course ministred by Tomas Cormen and Devin Balkcom.

• MIT - 6-006 - Well explained algorithms.

• MIT - 6-046j - Similar to the previous one, but with different algorithms.

• MIT - 6-00sc - An easy and well explained introduction to algorithms.

• Udacity Intro to Algorithms - Python-based Algorithms course.

• Algorithms in Motion - Beginner's algorithms course with fun illustrations, based on the book Grokking Algorithms

• YogiBearian YouTube Channel - Lots of well explained vidoes on various computer science subjects. Account terminated due to violations of Youtube Policies.

Books

The most highly regarded books to learn algorithms

• Algorithm Design - Pretty straight-forward.

• Algorithms - Problems explained with Java, OO good practices, visualizations, and free online resources.

• Data Structures Using C - The basic concepts and usages of data structures.

• Elementary Algorithms - An awesome book about algorithms and data structures.

• Grokking Algorithms - An illustrated book on algorithms with practical examples.

• Introduction to Algorithms - Essential!

• Swift Algorithms & Data Structures - A practical guide to concepts, theory and code.

• The Algorithm Design Manual - Easy to read and full of real world examples.

• The Art of Computer Programming - The Book.

Github Libraries

Implementations of the most classic algorithms in a wide variety of programming languages

• C

• CoffeeScript

• C#

  • by @shkolovy

  • by @aalhour

  • by @justcoding121

• C++

  • by @xtaci

  • by @PetarV-

  • by @faheel

• Erlang

• Go

• Java

  • by @jpa99

  • by @phishman3579

  • by @asmolich

  • by @psjava

  • by @jeandersonbc

  • by @pedrovgs

  • by @Erdos-Graph-Framework

  • by @deepak-malik

  • by @yusufcakal

• JavaScript

  • by @jiayihu

  • by @felipernb

  • by @nzakas

  • by @duereg

  • by @mgechev

  • by @trekhleb

  • by @ManrajGrover

• Objective-C

  • by @ EvgenyKarkan

• Python

  • by @nryoung

  • by @prakhar1989

  • by @laurentluce

  • by @nbro

  • by @keon

• Ruby

  • by @kanwei

  • by @sagivo

  • by @kumar91gopi

• Scala

• Swift

  • by @kingreza

  • by @waynewbishop

  • by @hollance

• Language agnostic

  • by @kennyledet

  • by @indy256

  • by @sagivo

  • by @patmorin

Online Judges

Online Judges to practice what you learned above

• A2 Online Judge - Online Judge and problem archive.

• ACM-ICPC Live Archive - Hundreds of problems from previous ACM-ICPC Regionals and World Finals.

• AIZU ONLINE JUDGE - Japanese Online Judge.

• Algo Muse - Research based algorithmic problems.

• Baekjoon Online Judge - Korean Online Judge. 10000+ problems. Supports 60+ languages.

• CS Academy - Holds online contests and IOI practice contests

• CodeChef - More problems and monthly online contests.

• Codeforces - The only programming contests Web 2.0 platform

• Codefights - Practive programming and tackle out your next tech interview

• CodeMarshal - Real world contests online!

• CodeWars - A website that houses support to solve algorithms in many languages in varying difficulty.

• CoderByte - A decent website with algorithm challenges from beginner to advanced levels. Supports most of the popular languages like C++, python, javascript, ruby.

• HackerEarth - Practice alogrithmic problems & challenges and participate in hiring challenges.

• HackerRank - Featured algorithm and functional programming online judges

• Infoarena - Romanian Online Judge. 1500+ algorithmic problems

• Kattis- Online judge and problem archive

• LavidaOnlineJudge - Korean Online Judge(Half English). 1300+ problems.

• Learneroo Algorithms Tutorials - Learn and practice algorithms by solving challenges online.

• LeetCode - Learn algorithms and prepare for interviews.

• PKU JudgeOnline - Chinese Online Judge.

• ProjectEuler - Mathematical problems that can be solved using algorithms (or just a pencil, depends on how much you already know).

• Rosalind - A platform for learning bioinformatics and programming through problem solving.

• ShareCode.io - Online Judge and contest host with a lot of algorithmic problems in the archive to practice.

• Snakify - An introductory Python course with 100+ algorithmic problems and a step-by-step debugger (from Russia).

• SPOJ - More problems.

• TopCoder - Lots of problems and real world/money worthy problems in Graphic Design, Data Science and Development.

• URI - Brazilian Online Judge. Not so much problems, but it's growing and it has online contests.

• UVA - Hundreds of problems (from previous ACM-ICPC Regionals, World Finals and others).

Tools

Some tools that can help you in the learning of algorithms

• interactive-coding-challenges - Interactive, test-driven coding challenges (algorithms and data structures).