Rosetta Code!

SoloLearn offers tools for learning to code across multiple languages, available across web and multiple mobile platforms. The mobile-first apps focus on learning through community interaction including sharing of user-generated content and head-to-head challenges.

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

The online programming practice in java and python.

Wanna pick up a new language without relearning code basics? DuoCoder is a language learning service by Jason Park