This CCC Online Grader is the system used to run the Canadian Computing Competition. It also provides access to practice problems and previous contests.
Offical Website: CCC Online Grader (Support Online Pratise with Judgment)
Past Contests: CCC Past Contest
This YACS Platform was open from March,2020 which is supported by Shanghai Computer Society.
Offical Website: 上海市计算机学会竞赛平台 (NOT Support Online Pratise with Judgment)
Past Contests: 题目集
Offical Website: USACO (Support Online Pratise with Judgment)
Offical Training: USACO Trainng (Support Online Pratise with Judgment)