Hello!

VK Cup 2015 — Round 1 (unofficial online mirror, Div. 1 only) — is public unofficial replay of Round 1. It means that if you didn't take part in VK Cup (for example, you are not Russian-speaking), decided to cancel further participation in VK Cup or didn't pass a Qualification you can take part in VK Cup 2015 — Round 1 (unofficial online mirror, Div. 1 only). You should be in Div. 1 to take part in it.

Mostly it will be typical round with regular Codeforces rules. Persons (not teams) will take part in it. The problems will be in English and in Russian. It will be hacks and rating will be updated after it. It will be used recently implemented smoother dynamic problem scores with 250 points steps. You can read about it here.

There were many not Russian-speaking teams in VK Cup Qualifications. I encourage these teams to respect the position of the organizers and not to take part in official Round 1. Please, take part in VK Cup 2015 — Round 1 (unofficial online mirror, Div. 1 only).

Wish you good luck!

Hi everybody! There will be a Codeforces Round for both divisions today at standard time set up by me.

My teammates from ICPC team Moscow SU Trinity sankear and malcolm helped me a lot while preparing this round, also there were lots of useful tips and advices from MikeMirzayanov, applause for them. English translation was made by our veteran translator Delinur.

As usual, there will be five tasks for two hours. The scoring will be announced later.

See you on the round! I hope that each contestant will be able to find something nice in ongoing problems.

UPD: Scoring is standard.

UPD2: Due to technical issues the round is delayed by 15 minutes. We are sorry for an inconvenience.

UPD3: We are sorry for an inconvenience with the task Div1-D. The pretest #16 wasn't satisfying the constraints n, m, k <= 200000. The system testing for the first division will be delayed. If you think that you were affected by this test, you may write me a message and we will make this round unrated for you.

The system testing for the second division will happen shortly, as usual.

UPD4: System testing is complete. Congratulations to the winners!

Div1:

1. piob

2. PavelKunyavskiy

3. dreamoon_love_AA

4. mnbvmar

5. aid

Div2:

1. happyBirthDayBeni

2. ExfJoe

3. _0029

4. tudort

5. kill-z

UPD5: the English editorial was added.

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!