Codeforces Beta Round #84
By witua, 13 years ago, translation, In English
Hello!

Welcome to Codeforces Beta Round #84! I am Vitaliy Herasimov (witua) and I am an author of today's problems. Thanks to Artem Rakhov (RAD) and Pavel Kuznetsov (it4.kp) for the help and advices in preparing of the rounds, Maria Belova (Delinur) for the statements translation.

Good luck!

Contest is over! Congratulation to winners!

Division 1:

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Codeforces Beta Round #83
By Atef, 13 years ago, In English
Hi all,

Today we would like to invite you to take part in round #83 inspired by the ACM practice sessions last year when Dima was visiting the German University in Cairo (GUC).

We have composed the problemset about life in Egypt and the GUC. Hope you will like it :)

The points for the problems in Div 1 & 2 will be: 500-1000-1500-2000-2500.

The writers of the problems are Dima and myself.

We would like to thank RAD, Connector, it4.kp, Delinur, and MikeMirzayanov, who greatly helped in preparing this contest.

We wish you a pleasant, educational and successful contest!

The editorial is under construction.

Good luck to everyone!

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Codeforces Beta Round #82 (Div. 2)
By Ripatti, 13 years ago, translation, In English

Good evening.

Today's round is mine, as the previous one. This round will be for participants of the second division. Participants of the first division can take part in the round out of competition.

RAD, Connector, it4.kp and MikeMirzayanov helped me to prepare this round. Delinur translated statements into English.

Contest will be in the good old tradition of Codeforces. No any innovations, pretty short and clear statements.

Points for problems are standard: 500-1000-1500-2000-2500.

Good luck everyone!


UPD. Round was ended, ratings was updated.

Winners:

1. tsundere

2. jte

3. abacadaea

4. ltaravilse

5. Billy_Herrington

Editorial.

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Codeforces Beta Round #81
By Ripatti, 13 years ago, translation, In English

Hello everyone!

I am the author of problems of today round. RAD, Connector, it4.kp helped me to prepere this contest. Delinur thanslated statements into english.

It will be a thematic contest. And the theme is Disgaea.

Is it possible to survive artef damage that is written by nine-digit number?
Of course, if amount of your health points is ten-digit number.
fans about Disgaea

Disgaea: Hour of Darkness is tactical RPG video game for consoles Playstation 2, PSP и Nintendo DS. So, get acquainted:

Etna, Laharl and Flonne - main characters of the game

The problems involves some aspects of the game mechanics. They are adapted for problems, therefore a bit different from original ones. Please use statements as formal documents.

Some problems have animated pictures. Please ensure that your browser supperts formats APNG or GIF.

Problem points will be standard for contests of Codeforces:
500-1000-1500-2000-2500.

Good luck!

UPD. The contest ended and ratings was recalculated.
:Winners:
1. KADR
2. neal
3. cerealguy
4. ivan.popelyshev
5. tourist

Editorial.

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Announcement of Codeforces Beta Round 81
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Codeforces Beta Round #80
By Alex_KPR, 13 years ago, translation, In English

Hi all!

Now it's time for 80th Codeforces Beta Round.

The authors of the contest are: Alex_KPR, winger, RAD, Connector, it4.kp. I hope all problems will be interesting for you and not extremely hard. ;)

Today is Connector's birthday — so, let's congratulate him together!

Good luck and have fun!
_____________________________________

Thank you for your action! =)

Top 10 participants in the first division are:

Place
 Who
1
  SergeiRogulenko
2
  hos.lyric
3
  Romka
4
  neal
5
  sdya
6
  KADR
7
  ftiasch
8
  niyaznigmatul
9
  dolphinigle
10
  AleX

There are only two participants who beat problem E: the winner of the contest SergeiRogulenko and MBabin who gets 76th place.

Top 3 participants in the second division are:

Place
 Who
1
  anrieff
2
  zplinti1
3
  Efgen

Congratulations and good luck at the next time!

Official tutorial will be added later. But AlexanderBolshakov already wrote the tutorial about most of problems.

Problems were translated by Delinur.
_____________________________________

Tutorial is here.

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Codeforces Beta Round 79
By Sammarize, 13 years ago, translation, In English

Hello!

I'm, Valeriy Samojlov, graduating student of SPbSU,  present you codeforces beta round 79. Today you will meet with boy Gerald and will help him to solve some living problems. 

Today we have usually cost of problems in both divisions: 500 - 1000 - 1500 - 2000 - 2500.

It my first codeforces round, I hope, problems will be interesting.

I want to thank Artem Rakhov (RAD) for big help with preparation of problems, Makar Krasnoperov (Connector) for some useful remarks and Maria Belova for translation.

Good luck for participants of both dovisions!


Contest is over! Congratulation to winners!

Division 1:

1. RAVEman

2. ilyakor

3. ACRush

Division 2:

1. SuperLight

2. xiaowuc1

3. Timur_Sitdikov

Editoral a appeared.

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Unknown Language Round #3
By amirali1374, 13 years ago, In English

Hi all!
Unknown Language Round #3 is going to take place on 30th of July. (This very Saturday -- Friday for some parts of the world)
This is the third contest of its type. The rules are easy (and fun):

  1.     Scoring is similar to that of ACM-ICPC.
  2.     The contest is not rated.
  3.     You can submit your code using only one language. This language is a secret and will be announced only when the contest begins! (We'll expect lots of coding bugs and syntax mistakes!)


This is the 100th contest on Codeforces. Congratulations to Mike Mirzayanov for developing a system that grows so fast!

There will be 10 problems overall. The tasks concentrate mainly on coding abilities rather than problem-solving and algorithmic techniques. Tasks are made by Mike Mirzayanov, Kiana Gholampoor, Soroush Farrokhnia , Amir Goharshady and Me (Amirali Mohammadzade).

We're grateful to Artem Rakhov for helping us to prepare the tasks, Maria Belova for translation, Zahra Rohanifar for testing one of the tasks and Hossein Boomari for teaching us to code!

The contest is dedicated to Mike Mirzayanov and Artem Rakhov for their great job at Codeforces and for helping us all improve our coding abilities.

UPD: The contest is over.Only 6 people solved problem J. Congratulations to Peter50216 from Taiwan for winning the contest and to the following 5 people for solving all the taks:

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Announcement of Unknown Language Round 3
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Codeforces: system maintenance
By MikeMirzayanov, 13 years ago, translation, In English
Codeforces will undergo scheduled system maintenance between July 25th and July 27th. On these days you may notice some problems in the Codeforces website or in the Codeforces judging system. If you encounter a problem, please wait a few minutes and try again. Thank you for your patience.

UPD: Work is finished, thank you all for your patience.
UPD 2: It appeared side-effect: TeX formulas, which are rendered in the images now looks supercontrast. I'll fix it soon.

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Codeforces Beta Round #78
By goryinyich, 13 years ago, translation, In English
Hi there!

Me - Sergey Vedernikov - is the author of today's CF beta round.

During the round you'll assist far away kingdom citizens in solving everyday problems, and sometimes - just to fight for your survival.
This round is "red" =), therefore the problems should not appear too difficult, and you should get pleasure from solving them.
To those who know Russian language I recommend to read problem statements in Russian. Not because of the quality of translation - English just poorly communicates Russian folklore language style.

Finally I want to thank Artem Rakhov for invaluable help during the round preparation, Maria Belova for the qualitative translation of the problems, Mikhail Mirzayanov for excellent CF system and all participants for not leaving this event without your attention.

More AC verdicts and high rating to all of you! gl & hf

UPD: Unfortunately, problem B (div. 1) / D (div. 2) appeared to be more difficult, and author's solution appeared wrong. The round will be unrated. I apologise for this to all participants.

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Congratulations to Yandex.Algorithm winners!
By Michael, 13 years ago, translation, In English

Congratulations to Petr Mitrichev (Petr), the Yandex.Algorithm 2011 Champion!

Congratulations also to Dmitry Dzhulgakov (dzhulgakov), Makoto Soejima (rng_58), Ivan Metelsky (ivan.metelsky), Alexey Levin (levlam) and Gennady Korotkevitch (tourist) who placed 2, 3, 4, 5 and 6 respectively! They solved as many problems as the champion. Full results are available here

Problems turned out to be really difficult: nobody managed to solve more than 3 problems during the 2 hours of competition. Problem A was considered much simpler than all others by the contest authors, but less than half of participants could solve it, and even the champion lacked 30 seconds to fix the last bug. Only one coder could solve problem E: Xhark from Korea.

Problem E was suggested by Ilya Kornakov (ilyakor) who is also a developer in my group at Yandex :) Problem A about domino and a guy named Gena was powered by Ivan Popelyshev (ivan.popelyshev). Problem B — Stanislav Pak, C — Denis Yarets. All three are also our employees. Problem D was suggested by Artem Ripatti. My problem was rejected at the last minute, so it will wait for you at the Petrozavodsk training camp :)

Thanks to all finalists, authors, participants out of competition, contest organizers, MIPT for the accomodations and the main sponsor — Yandex.

Good luck to everybody who competes in the OpenCup onsite today!


A few more photos from the competition:

Petr and our foreign guests rng_58, wata and dolphinigle
ivan.metelsky, MikeMirzayanov and pieguy

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