MAGICHF2 Testdata Error

Hello everybody,

It has been announced that an error was discovered in MAGICHF2 testdata, it has been fixed now. Before that, my solution had an AC, but now I get a WA and can’t figure out how to fix that. Does anyone know what kind of error the ancient testdata has ? I can’t figure out if my idea is totally wrong or I just need to find a way to fix it.

Thank you.

I am feeling there is still some error in the test cases. There are many people(including me) who AC’ed 2nd subtask but not the 1st one. Given that the 1st is subset of 2nd, how is it possible?


It is possible If some corner cases are present in smaller subtask. But they are not included in larger subtask.


I’m not sure which side of the line you are on here, regarding banning discussion of problems in ongoing competitions.

I feel its on the not allowed side. Because the information can be directly utilized to get AC XD.

1 Like

@aryanc403 exactly…
@jastiger I faced the same issue but now I got 100. Test data seems correct.

My only concern is why am I even getting 75 pts if the solution is not completely correct. Splitting the problem in subtasks should not be aligned with correctness of solution.


There are options know by name of “closed” or “delete” xD.

This is codechef, @jastiger, I remember it happened earlier too in problem K-Compression, where wrong solutions (even for small test cases) passed first subtask but not second, while ideally they shouldn’t pass any,

What I don’t understand is why there is only 2 tasks in that question when creating tasks for such questions are extra easy.