Hello.

The round 1 of VK Cup 2017 will take place on March 18 at 18:35 MSK (check your timezone here), along with standard div1+2 Codeforces Round #405. The contest "VK Cup 2017 — Round 1" is for teams qualified from two Qualification Rounds. The top 400 teams will advance to the Round 2, while other ones will have one more chance in the Wild Card Round 1 in April. Those who don't participate in the VK Cup can take part in the Codeforces Round #405 individually (problems will be available in English too). All three rounds last 2 hours, and all are rated.

I want to thank: KAN for his help in the contest preparation, MikeMirzayanov that we are here, AlexFetisov for testing, the VK company for this nice annual contest.

I'm a setter and I hope (and expect?) that you will enjoy the problems. During the contest, remember that you can read many problems and try to solve those that fit you most.

I wish you great fun and no frustrating bugs.

div2: 500-1000-1500-2000-2500
div1: 500-1000-1500- 2250 -2500
vk-cup: 250-500-1000-1500- 2250 -2500

The contest is over. See the editorial here. Congratulations to all who advanced to the next round, and congratulations to winners of each contest.

Specifically, the winners of VK Cup Round 1 are:

1. Zlobober, zemen
2. LHiC, V--o_o--V
3. Arthur, kefaa
4. map, Babanin_Ivan
5. felix, Trumen

The winners of parallel rounds are:

Div. 1:

1. -XraY-
2. Laakeri
3. Lewin
4. dotorya
5. RAVEman

Div. 2:

1. rupxup
2. YES_RPG
3. T0RRES
4. HXLLL
5. Len

I'm sorry for letting some slow solutions pass in the Rectangle Strips problem. I tried really hard to prepare tests there but apparently didn't succeed.

Hello, Codeforces!

Tomorrow, in March 15, 2017 at 18:05 MSK a regular rated Codeforces round for participants from the second division will take place. As usual, participants from the first division can take part out of competition. It's my second contest and I hope you'll like it more than my previous one.

As usual, there will be five problems on the contest and two hours to solve them. I advice you to read all the problems' statements attentively. Also check all your solutions for correctness even if they passed all the pretests. Verdict Pretests passed doesn't mean that the solution is completely correct! I wish you to enjoy the contest and learn something new solving the problems.

Like in the last time, the problems will be about Anton and his friends.

Great thanks to Alexey Vistyazh (netman) for help in preparing the contest, Vladislav Vishnevsky (Vladik) for testing the round, Dmitry Klebanov (dmitriyklebanov) for reading the statements carefully, and of course, Mike Mirzayanov (MikeMirzayanov) for the great platforms Codeforces and Polygon.

Scoring distribution is 500 — 1000 — 1500 — 2250 — 2500.

UPD. The contest is over, system testing has already started, the editorial will appear soon.

UPD2. Editorial has arrived.

UPD3. Congratulations to the winners of the contest!

Div. 1

1. uwi
2. rajat1603
3. SaSa
4. mr.banana
5. Kaban-5

Div. 2

1. CommonAnts
2. Gauss
3. binsjl
4. hotwater
5. mister_dudec

Thanks everyone for participating :)

Hello everyone!

It looks like there are a lot of Facebook users on Codeforces. But they could not easily authorize with their Facebook account until now. Well, now they can!

You can connect your Codeforces account with your Facebook account on profile settings page:

Just click the connect/update button, allow Codeforces to have access and save settings.

Besides that method, you can also connect your accounts while authorizing — if your Facebook account is not yet connected, you will be asked to either create a new account or to connect it with existing one.

To connect with an existing account you will need to log in using already known method.

Hello, Codeforces!

In the lead-up to the ACM-ICPC World Finals we invite everyone to participate in Moscow Pre-Finals ACM ICPC Workshop, that will be held 10-17 of April 2017 at the campus of the Moscow Institute of Physics and Technology ( MIPT). The event is organized by one of the leading Russian universities, MIPT and ITMO.

The Moscow Pre-Finals ACM ICPC Workshop is the unique event in the world of competitive programming. Every year teams from 20 different countries from Europe, Asia and the USA meet at one platform. Many teams participated in this Workshop turn out to be the prize-winners and winners of the the ACM-ICPC World Finals. In 2016 8 out of 13 teams that were awarded medals at the Finals took part in the Moscow Pre-Finals Workshop ACM ICPC at MIPT.

This year the organisators have made possible the remote participation which includes: 2 consultations (1,5 hour each); access to the contests; access to the contest-analysis; electronic certificate for the team; the lower price: the cost for one teams is 1300$. If you want to participate remotely or you have any questions, write here: [email protected]

The Workshop is going to be held in accordance with the two divisions scheme. We invite finalists to participate in the first division (Div.A) and other teams who want to train before the next season in the second division (Div.B). The official language is English.

The participation cost for one person is $590. The cost includes the full curriculum, food and accommodation at the MIPT campus, as well as the sports and sightseeing schedules on days-off. Registration is here

Also, before the Workshops, we invite the teams of division B to participate for free in the contest, which gives you the discount on participation in Moscow Pre-Finals ACM ICPC Workshop! (1st place — 50% ; 2nd place — 30%; 3d place — 20%)

UPD Thanks to all the participants and our congratulations to the winners!

1 Samara U 2

2 Lords of (the) Homeless

3 Daddys

Hi everybody.

Deadline24 is an international programming marathon, organized continually since 2009 by Future Processing. During the contest, the teams of three tackle algorithmic problems.

The marathon is composed of two phases. The qualifying round starts on March 12. For 5 clock hours, the teams will be solving tasks and generating responses assessed by the verification server. This stage of the competition is remote. Then, the best teams of the qualifying round will meet at the 24-hour finals held on April 22-23, 2017, in Katowice (Poland).

The teams can sign up until March 9, 2017 (23.59 CET). Registration is available on the contest website www.deadline24.pl.

You can get familiar with the type and difficulty level of the tasks in the Qualifying round by competing in the GYM contest on this Thursday and will last 5 hours (check your timezone here). It will be a replay contest of the Qualifying Round 2016. The contest will appear in Codeforces GYM soon. Because of technical limitations, the scoring and final ranking system of that replay contest is not identical to the one used during the qualifying round — don't forget to visit the contest website (www.deadline24.pl) to read full rules (e.g. submitting time matters and you submit output files instead of codes).

I'm not one of organizers but I competed in some of previous editions and I enjoyed finals a lot. Now I was asked to help a bit with the GYM replay. On behalf of the organizers, I want to thank Mike Mirzayanov for his help in promoting the competition on CF.

Don't forget that the registration ends on Thursday! Good luck in the qualifying round.

UPD: the GYM contest will start with the delay of 30 minutes. Sorry for the inconvenience.

Hello everybody!

The Technocup 2017 (a competition for high-school students hosted by Mail.Ru Group together with MIPT, Bauman MSTU and Codeforces) Finals is happening tomorrow in Moscow. For those who will not participate in the Finals, we prepared mirror contests for both divisions. The round will start at 13:05 UTC at Sunday, March 5th, 2017 and will last for two hours.

The round was prepared by Endagorion, WHITE2302, Alladdin, fcspartakm, Amethyst1, MikeMirzayanov, ifsmirnov and me.

You can view the current onsite results at link.

There will be six problems in each division.

Editorial is here.

Hi, Codeforces!

Codeforces Round 402 (Div. 1) and Codeforces Round 402 (Div. 2) are going to happen on February, 26th, at 08:05 AM UTC. The round will run at the same time with Innopolis University Open, Olympiad in Informatics. Division 1 problems are the same as olympiad problems. Some of Division 2 problems are prepared by MikeMirzayanov, thanks to him.

The problems are developed by MikeMirzayanov, YakutovDmitriy, VArtem, FireZi, burakov28, pashka.

We hope you enjoy the problems!

UPD:
problem scores for div1: 500 — 1000 — 1500 — 2250 — 2250
problem scores for div2: 500 — 1000 — 1000 — 1500 — 2000 — 2500

UPD 2: Congratulations to winners!

Top-10 (Div.1)

1. bmerry
2. ainta
3. Marcin_smu
4. kcm1700
5. jqdai0815
6. anta
7. FizzyDavid
8. Reyna
9. dotorya
10. gs12117

Top-10 (Div.2)

1. Chiaki.Hoshinomori
2. WhyamIhere
3. 2021
4. Schemtschik
5. kiiiiii
6. chakred_namor
7. marcospaulo
8. fushar
9. safarisoul
10. Panole233

Editorial is here.