List of Top Websites on Compititions

A2 Online Judge. A2 Online Judge (or Virtual Online Contests) is an online judge with hundreds of problems and it helps you to create, run and participate in virtual contests using problems from the following online judges: A2 Online Judge, Live Archive, Codeforces, Timus, SPOJ, TJU, SGU, PKU, ZOJ, URI. It also helps you to manage and track your programming comepetions training for you and your friends. It helps for ICPC ACM and IOI training also.