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Timus Online Judge is the largest Russian archive of programming problems with automatic judging system. Problems are mostly collected from contests held at the Ural Federal University, Ural Championships, ICPC Ural Regional Contests, and Petrozavodsk Training Camps.
Timus Online Judge provides you an opportunity to participate in online versions of many contests held at the Ural Federal University on a regular basis. See the rules of online contests.