The AI Games!

A fun social platform for hackers to solve interesting puzzles, build quick hacks, code game bots and collaborate to solve real-world challenges.

Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.

CodinGame is a challenge-based training platform for programmers where you can play with the hottest programming topics.

SPOJ (Sphere Online Judge) is an online judge system with over 315,000 registered users and over 20000 problems. The solution to problems can be submitted in over 60 languages including C, C++, Java, Python, C#, Go, Haskell, Ocaml, and F#. SPOJ has a rapidly growing problem set/tasks available for practice 24 hours/day, including many original tasks prepared by the community of expert problem setters associated with the project.

Halite is an artificial intelligence programming challenge.

Built by CodeFights, Code Arcade challenges players to solve programming tasks to complete game levels. It's a fun way to hone coding skills.