Educational Codeforces Round 86 (rated for Div.2) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1342

Codeforces Round 638 (Div. 2) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1348

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

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

Testing Round #16 (Unrated) starts in ~4 hours. Please, join by this link https://codeforces.com/contests/1351

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

🔥New! Codeforces Round 640 (Div. 4) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1352

Codeforces Round #641 (Div. 1, Div. 2) starts in ~3 hours. Please, join by this link https://codeforces.com/contests/1349,1350

Codeforces Round 642 (Div. 3) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1353

Codeforces Round 643 (Div. 2) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1355

Educational Codeforces Round 87 (rated for Div.2) starts in ~4 hours. Please, join by the link https://codeforces.com/contests/1354

Codeforces Round 644 (Div. 3) starts on 24th of May at 13:35 UTC.
Please, join by the link https://codeforces.com/contests/1360?locale=en

Codeforces Round 644 (Div. 3) starts in ~2 hours. Please, join by the link https://codeforces.com/contests/1360?locale=en

Codeforces Round 645 (Div. 2) starts on 26th of May at 14:35 UTC.
Please, join by the link https://codeforces.com/contests/1358

Codeforces Round 645 (Div. 2) starts in ~2 hours. Please, join by the link https://codeforces.com/contests/1358

Educational Codeforces Round 88 (rated for Div.2) starts on 28th of May at 14:35 UTC. Please, join by the link https://codeforces.com/contests/1359

Educational Codeforces Round 88 (rated for Div.2) starts in ~2 hours. Please, join by the link https://codeforces.com/contests/1359

💥Kotlin Heroes: Episode 4💥 starts on 29th of May at 14:35 UTC.

The round is unrated.

- Top three winners will get prizes of $512, $256 and $128 respectively;

- Top 50 will win a Kotlin Heroes t-shirt and an exclusive Kotlin sticker;

- Competitors solving at least one problem will enter into a draw for one of 50 Kotlin Heroes t-shirts.

We will be glad to see you among the participants!

Please, join by the link https://codeforces.com/contests/1346

🔥Kotlin Heroes: Episode 4 🔥(unrated, 100 t-shirts + cash prizes) starts in ~2 hours.

Please, join by the link
https://codeforces.com/contests/1346