We're really sorry for the inconvenience in the contest Codeforces Round #482 (Div. 2) today.
It is our fault that the statements, especially the statement of the B problem, were absolutely ambiguous. I understand that many of you are frustrated, angry or even hate the contest. Moreover, we want to apologize for the weak pretests on problem A and B. We intended the problems to have many corner cases, yet failed to include those corner cases in the pretest.
We have been waiting for a really long time to present to you our creations, to make the community happy. But instead, what we just did was such a mess.
As the last words, we are really thankful for joining our contest, and we also apologize for all the mistakes that we've made during the preparation of the contest.
Please take this apology with an open mind.