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The website is unavailable. I'm working to fix it. Mike.

The website is up.

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Codeforces Round #639: the round is rescheduled.

Hello, Codeforces!

Unfortunately, I report that I decided to reschedule this round. I'm afraid that something might go wrong. Some strange database behavior has appeared, which leads to slow operation in completely unexpected places (it never was and should not be). I will work hard to fix it. My recent tests show that this can dramatically increase judging time (and leads to a huge queue). I don't want to risk the efforts of the writer, the coordinator, testers, and your time. Sorry about it, I was trying to fix it for many hours but I need more time. Hope it will be a great round!

Mike.

UPD: I temporarily rescheduled it on May, 6. But I'll discuss the date with the writer and coordinator and reschedule it again to the date they want.

Codeforces Round #639 (Div. 1, Div. 2) starts in ~4 hours. Please, join by this link https://codeforces.com/contests/1344,1345

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Please, help us to test the system under a load.

Hello! To be absolutely sure that the system technically works well, we moved the upcoming Div1/Div2 round, but on the same day (May, 9) we put the first experimental Div4 round! All details on the link: https://codeforces.com/blog/entry/77028

— MikeMirzayanov

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