Hosts regularly scheduled programming contests and ranks participants via an Elo-based rat · Interactive problems where solution exchanges data with an interactor · Rated competitive programming rounds for both Div. 1 and Div. 2 contestants · Programming competitions and contests, programming community

On the other hand, it is a platform where contests are held regularly, the participant's skills are reflected by their rating and the former contests can be used to prepare.

Programmers interested in and taking part in programming contests. · programming community · Students in China and other UTC+8 time zones

Codeforces is a project joining people interested in and taking part in programming contests.

Training and learning platform for programming contest preparation. · Programming competitions and contests · Training problems available in Codeforces gym section · Hosting rated competitive programming rounds

we plan to improve the platform to give the participants the opportunity to organize their own contests, filling the project with learning content, developing Codeforces as a training and learning platform.

Third-party code may be used in contest solutions only if it was written and published/dis · Many weekday rounds start late for UTC+8 users (around 22:35 or 23:35 local time)

Solutions and test generators can only use source code completely written by you, with the following two exceptions: - the code was written and published/distributed before the start of the round,

Participation is free

Participating in them is free and open to everybody.

Supports third-party login and integrations: Google OAuth, Facebook Authentication, YouTub · Third-party Android app ContestDeck integrates Codeforces, CodeChef, AtCoder, and LeetCode

Google OAuth is a registration and authentication service provided by Google Inc. and is connected to the Google network.