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Is it possible that mod 0 on Domjudge will return WA?
By Jelefy, history, 2 months ago, In English

Hi guys,

The context is, in problem H of the just finished APAC Championship (https://mirror.codeforces.com/contest/2206/problem/H), our first code did not deal with the case where there are equal ai's, and it got Wrong Answer in the contest. However, when I tested on Codeforces, it got Runtime Error verdict on the 3rd test case, which is just the next test case other than the 2 examples given.

So, is it possible that mod 0 on Domjudge will return WA? This was one of the major reasons that caused us not to qualify to WF, we wasted ~30 mins because of the WA verdict and thought that our solution was wrong.

Thanks.

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Mod 0 is equal to a division by 0 and it is undefined behavior. Runtime error on Codeforces is caused by diagnostics that Domjudge does not have (actually, i am not sure that diagnostics are throwing RE, but the main rule that with UB, you won't know if it will give you WA or RE or something else).

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