Codeforces Round #373 (Div. 1 + Div. 2) will take place on 23 September 2016 at 16:05 MSK. Please note that the timing is unusual.
This time tasks for you were prepared by me (Matvey Aslandukov) and my brother _XuMuk_ (Andrew Aslandukov). It is our first codeforces round and we hope you'll enjoy it. We want to say special thanks to Seyaua (Ievgen Soboliev), AlexFetisov (Alexandr Fetisov) and winger (Vladislav Isenbaev) for testing the problems, GlebsHP for his help with the contest preparation, and MikeMirzayanov for the excellent platforms Polygon and Codeforces.
Coincidentally, the date of the round falls on my birthday, so I am very happy that I can spend that day surrounded by our friendly community :)
There will be five problems and two hours to solve them. Traditionally, the scoring distribution will be announced later.
Div. 2 : 500 1000 1500 2250 2250
Div. 1 : 500 1250 1250 2000 2500
The problems are sorted by difficulty but as always it's recommended to read all the problems.
Contest complete! Thank you all for participating :)
Unfortunately, as noted Um_nik, many solutions of div.1 B task, including the author's, were incorrect. Now we are working on this problem. If we still manage to find the right solution and answers on pretests will be the same, the round may be rated. Otherwise, it will be unrated.
Thus final results significantly delayed. We apologize for the situation. If you have thought about the correct solution — write to us.
We made a decision to start system testing with the current solutions and tests. The question will be round either rated or not is still opened.
After considering different option and estimating their pros and cons, Codeforces team decided that the main factor to make a decision on whether the round should be rated or not is how much the bug affected the results.
In the second division, only two participants managed to implement the correct greedy algorithm for the original incorrect version of the problem D, thus we consider the effect of this problem on the final standing to be negligible. The contest for division two will be rated.
Things are very different for division one, as there were plenty submission to problem B and problems B and C took the most part of participants worktime during the contest. Assuming this fact we suppose that this bug affected the final results a lot and there is no way to consider its influence on each particular participant. As a result, the contest for division one will be unrated.
The only thing left to do is to apologize to the participants. We will do our best to avoid such situations in the future.
Congratulations to the winners!
Editorial is ready!