[ACM] recommended OJ

1> http://poj.org/

Features: There are a lot of questions, there are various sorting of submitted results (running time, memory size, code length, etc.), you can optimize various goals, sometimes the question is not just for AC, isn't it?

Http://codeforces.com 2>

Features: the interface is more beautiful, and most of the questions are relatively simple. It is suitable for beginners like me, and you can view the Code submitted by others (this is the most important for me, not for plagiarism, but for learning ). Occasionally participate in the competition to get a little sense of accomplishment. If an error occurs, you can view the test data.

3> http://acm.mipt.ru/judge/login.pl? Lang = en

Features: supports multi-language submission, including lua.

4> http://acm.timus.ru/

Feature: each question has a difficulty score. The smaller the number of people passing through the score, the higher the difficulty score.

5> http://www.51nod.com/onlineJudge/problemList.html! GroupId =-1

Feature: it is the OJ developed by litaoye danniu. Currently, there are many mathematical problems, but there is a good atmosphere for discussion. If you don't ask litaoye directly, just do it. Generally, questions are stored in the cluster. The previous test can view the test data and open the code as needed.