Hi everyone!

If you still remember, 5 months ago I added the ACM ICPC Vietnam National 1st Round into Gym.

This weekend, we're going to add the 2nd round from our National contest. We hope that this will help ease your hunger for contests :)

• The contest was designed to be harder than last time
• It consists of around 10 problems, and lasts for 5 hours.
• Teams are welcomed.
• Normal ACM rules is used.
• To those who's going to ask if it is rate): No contest from gym is rated.

The gym contest is prepared by laoriu, khuebeo, ngfam_kongu and me, I_love_Hoang_Yen. The problem setters are Vietnamese professors and some ex-ACM ICPC competitors.

We hope that there's going to be at least one interesting problem for everyone. Please join & have fun with us! May luck be with you :)

UPD: Contest is over. This is scoreboard of real contest: link

UPD2: Solution to some problems: link

UPD3: It turns out that the author's solution for problem F is wrong. I'm very sorry for that and I'm trying to fix it. I hope that it didn't make too much impact for any team. The bug was found by team Orz xyz111 (apia, PoPoQQQ1, alpq654323). You are really awesome, not only solve the problem, but solved it despite the fact that the test might be wrong.

UPD4: Solutions of F has been rejudged. It looks like the mentioned team was the only team who was affected. I am very sorry for that.

Hello, Codeforces!

On March, 2nd at 10:00 MSK Codeforces Round #295 will be held in both divisions.

The round will be held at the same time with Winter Computer Camp olympiad, the problemsets will be highly similar. The problems are by me (Endagorion) and Evgeny Savinov (savinov). The problems are prepared by members of the Winter Computer Camp technical committee: Georgy Chebanov (gchebanov), Filipp Rukhovich (DPR-pavlin), Alexander Mashrabov (map), Sergey Kiyan (sokian), Konstantin Semenov (zemen), Kinan Alsarmini (Sarkin).

Big thanks to Max Akhmedov (Zlobober) for his help with preparing the problems, Maria Belova (Delinur) for translating the statements in English, and Mike Mirzayanov (MikeMirzayanov) for creating Codeforces and Polygon systems.

The scoring is standard for both divisions: 500-1000-1500-2000-2500.

Please note that the Winter Computing Camp olympiad is scheduled to finish later than the Codeforces round. Thus, we ask you not to discuss the problems and solutions in the comments until 14:10 MSK. Also, viewing of other participants' solutions will be closed until that time. The editorial will also be published later.

UPD: you are free to discuss the problems now.

UPD2: the editorial is finally up! Sorry for the delay.

Also, grats to our Div.1 winners:

1. Petr
2. hos.lyric
3. Syloviaely
4. andrew.volchek
5. xyz111

Special respect goes to Petr and rng_58 for solving the hardest problem E!

Hello, Codeforces!

My name is Adilet Zhaxybay, and together with Bekzhan Kassenov (BekzhanKassenov) we are authors of Codeforces #294, which will be held on 28th of February at 16:00 MSK. This is our first Codeforces round and we are happy to invite all of you to participate in it. The round will be rated for the second division, however, participants from the first division can, as usually, participate in it unofficially.

As far as we know, it is the first Codeforces round, which was completely prepared by the authors from Kazakhstan. We are very honored by this fact and hope that everything will go great. We are encouraging other participants from our country to join us — I am sure, that you can prepare a lot of very nice problems. Preparing Codeforces round is possible ;)

We want to thank all the people, who helped us to prepare the contest: Max Akhmedov (Zlobober), who helped us with the problems, Nurlan Kanapin (kt-9) and Mansur Kutybaev (mexmans), who tested the round, and Maria Belova (Delinur), who translated problem statements.

Also we want to say great thanks to Mike Mirzayanov (MikeMirzayanov) for creating Codeforces and Polygon. We want to congratulate Codeforces with its fifth anniversary. We, authors of the round, were very lucky to start competitive programming at the time, when Codeforces already existed, and it helped us really a lot!

We love, when authors of the round write a bit about themselves (we encourage everybody to do so) — this helps to feel that there are real people behind the problems. Thus, we will write a bit about ourselves. We are students from Nazarbayev University (nu.edu.kz). NU is a new university with English as a language of teaching, which is located in the capital of Kazakhstan, Astana. Our university participates in ACM-ICPC only from 2012, but the team from NU already qualified to World Finals twice — in 2014 and 2015. We hope that we will do only better in the future!

Good luck to all!

UPD Score distribution will be standard (500 — 1000 — 1500 — 2000 — 2500)

UPD2 Editorial is available here

Congratulations to winners!

1. AkashiSeijuro

2. fmzbtf937

3. mxh3777

4. IGandWFin2019

5. ruozha2 & i_hate_t0nzuk

Round is over, thanks to everybody, who took part in it!

Hello, friends!

Yes, this post is for friends of Codeforces. Recently Codeforces had 5 years birthday. And on this occasion we opened a campaign to raise funds for the operation and development of Codeforces.

We are eager to develop and move forward and look forward to your participation in the campaign.

We invite you to consider the possibility to support Codeforces. Details of the campaign can be found at its direct link.

Mike Mirzayanov

UPD: We have great news!

Hello, Codeforces!

I'd like to invite you to Codeforces Round #293 (Div. 2). It will be held on Tuesday, February 24 at 19:30 MSK and as usual Div. 1 participants are invited to join out of competition.

Great thanks to Maxim Akhmedov (Zlobober) for helping me preparing the contest, to Maria Belova (Delinur) for translating the statements into English, to Mike Mirzayanov (MikeMirzayanov) for the great Polygon platform and ideas of some problems and to my dear friends Pavel Kholkin (HolkinPV), Arthur Svechnikov (ikar) and Vitaliy Kudasov (kuviman) for writing solutions.

It will be a little unusual round — you will be given six problems and two and half hours to solve them.

UPD Score distribution will be 500-1000-1500-2000-2500-2500. Good luck everyone!

UPD2 Competition completed! Thank you all!

UPD3 You can find editorial here.

UPD4 Congratulations to the winners!

1. urkkvr145
2. 0o00oo0o000oo00o
3. sorry_t0nyukuk
4. NgocHai
5. GintokiSakata

Hello, everyone! Codeforces Round #292 will be held at Feb/17/2015 19:30 MSK. We're looking forward to your participation!

The problems are from dreamoon_love_AA, and thanks Shik for some discussion. Also we want to thank Zlobober for helping me prepare the round, AlexFetisov and winger for testing this round , Delinur for translating the statement into Russian, and MikeMirzayanov for Codeforces and Polygon.

This is first time I provide all problems for a Codeforces round. I hope you'll find it interesting! Please read all problem statements and discover what the main character drazil do in those problems for he's really cute =)

Finally, I would like to ask sorry_dreamoon to participate this round. I believe everyone have the same curiosity as me about your behavior in Dreamoon's round =) May I have the honor of inviting you?

Update1 : Because problems of this round are hard to determine their difficulty, We will use Dynamic score for this round. Then the order of problems is from easy to hard by sense of me and testers.

Update2 : Due to technical reasons we have to move round on five minutes.

Update3 : Congratulation to our winners:

Div 1:

1. Haghani

2. sorry_dreamoon

3. Endagorion

4. jcvb

5. xyz111

Also, special congrats on rng_58, who solved problem E in Div.1, which anyone else could not solve.

Div 2:

1. EarthQuito

2. I.Smirn0ff

3. zclimber

4. Chipe1

5. tylerbrazill

Between them, EarthQuito is the only person who solve all problems!

Update4 : link to editorial

Hello, Codeforces!

I'd like to invite you to Codeforces Round #291 (Div. 2). It'll be held on Saturday, February 14 at 19:30 MSK.

Great thanks Maxim Akhmedov (Zlobober), Vasya Antoniuk (Antoniuk) for helping me preparing the contest, to Maria Belova (Delinur) for translating the statements into English, to Mike Mirzayanov (MikeMirzayanov) for the great Polygon platform.

Good luck everyone!

UPD: Score distribution will be the next — 500-1000-2000-2000-2500.

UPD: Editorial. Sorry for the delay)