Older releases on Google Code: https://code.google.com/p/bnuoj

An Online Judge system for Beijing Normal University, featuring following awesome functions

• Basic online judge functions;

• Virtual judge functions, including loads of OJs;

• Replay contests and merge standings;

• Contest with challenge sections, like Topcoder and Codeforces;

• Problem categories, delicious for new comers.

And it's still developing!!

Version 3:

https://www.bnuoj.com/v3

https://acm.bnu.edu.cn/v3

https://oj.51isoft.com/v3

Version 2:

https://www.bnuoj.com/bnuoj

https://acm.bnu.edu.cn/bnuoj

https://oj.51isoft.com/bnuoj

Version 1:

https://www.bnuoj.com/contest

https://acm.bnu.edu.cn/contest

https://oj.51isoft.com/contest

OI version:

https://www.bnuoj.com/contestoi

https://acm.bnu.edu.cn/contestoi

https://oj.51isoft.com/contestoi