By Nickolas, 11 years ago, translation, In English

Unfortunately, the most anybody could solve was 7 problems out of 9 total. 1289 participants solved at least one problem — this is less than the last year's numbers, but not bad either. Anyways, the key point is the total quantity of fun the people had!

409A - The Great Game

The Most Intellectually Challenging Game In The World turned out to be the famous rock-paper-scissors. One could deduce this from the examples — ok, the rock () didn't look itself, but paper [] and especially scissors 8< looked really lifelike!

Team competition is organized like this: players are split into pairs, with one player of each team in each pair, and pairs play against each other (the first line of input has "moves" of first team's players, the second line — of second team's players). The team which scores more individual victories wins.

By the way, the game is not so trivial as it looks -

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By Nickolas, 11 years ago, translation, In English

The contest is over; I hope you've enjoyed it :-) Editorial is here. See you next year!

The third April Fools Day Contest will take place on Tuesday April 1st. This is a joke competition in which solving the problem is often easier than figuring out what the actual task is. Thanks to kit1980, Skiminok, Gerald and MikeMirzayanov for their help in preparing problems.

In this round you'll be given several weird problems (the estimated quantity is between 6 and 10) and 2 hours to solve them. The contest will use ACM ICPC rules (no hacks, the standings are decided by the number of solved problems and penalty time earned on them), and it will be unrated. You can submit solutions in any language allowed by Codeforces — well, unless the problem says otherwise :-)

Be warned, to enjoy competing in this round you'll need a sense of humor compatible with mine! Good luck, and have fun!

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By izban, 11 years ago, translation, In English

Hello everyone!

This Sunday, on March 30 at 11:00 MSK (March 30 at 07:00 UTC), Codeforces Round #239 for both divisions participants will take place. Note the unusual time of the round.

The problems have been prepared by me. I want to thank Codeforces team: tasks coordinator Gerald Agapov (Gerald) for invaluable contribution to the preparation of tasks and Maria Belova (Delinur), who has translated the problems. Also thank to Niyaz Nigmatullin (niyaznigmatul) for testing.

I wish you all good luck and have a good weekend!

UPD: You can see score distribution at the problems page.

UPD2: You can find editorial here.

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By gen, 11 years ago, In English

Hello everyone!

Codeforces round #238 will start today at 19:30 in Moscow time. The round will be held in both divisions.

The round was prepared by me and cfk. This is the 4th round for me and the 2nd for Krisjanis. I think the problems this time are rather unusual and maybe even surprising. We have no doubt that everyone will find a problem that suits their taste! But you have to find it. (:

As always, thanks to Mikhail Mirzayanov (MikeMirzayanov) for Codeforces and Polygon systems, and Maria Belova (Delinur) for translating the statements. Big thanks to Gerald Agapov (Gerald) for helping in preparation of the contest. Me and Gerald had a chance to talk about the problems onsite during the Petrozavodsk winter camp, which I think was very productive.

We wish you a very exciting round!

UPD1: Score distribution:

DivI: 500 1000 2000 2000 2500

DivII: 500 1000 1500 2000 3000

The scoring for the problems is relative, so that the cost of each problem would be a multiple of 500 and closer to the objective estimate. Don't be afraid, the problems are not really that hard. (:

UPD2: Congratulations to the winners!

DivI:

  1. al13n
  2. Shef
  3. scott_wu
  4. sillycross
  5. Komaki

DivII:

  1. NelsonMondialu
  2. L_Ecry
  3. aaaaAaaaaAaaaaAaaaaA
  4. xorfire
  5. Hec

UPD3: Excellent round statistics from DmitriyH.

UPD4: The contest tutorial is published here.

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By Igor_Kudryashov, 11 years ago, translation, In English

Hi to all!)

Regular round Codeforces #237 for participants from 2 division will take place tomorrow March 19, 19:30 MSK. Traditional, participants from 1 division can take part out of the competition.

The problems were prepared by Igor Kudryashov (Igor_Kudryashov) and Gerald Agapov (Gerald). Also thanks to Michael Mirzayanov (MikeMirzayanov) for very cool system Codeforces and Mary Belova (Delinur) for translating the problems into english.

We wish everyone good luck, high rating and excellent mood)

UPD: Score distribution will be standard 500 — 1000 — 1500 — 2000 — 2500.

UPD 2: The contest is over, thanks to all participants.

Congratulations to the winners:

  1. Pkqs09
  2. juggler
  3. zstu_bobo
  4. kevinswat
  5. Salvare004

UPD3: You can find the tutorial here

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By MDovzhenko, 11 years ago, translation, In English

The CROC company and the Ministry of Defense of Russian Federation invite the schoolchildren of the 9-11th years of education in Moscow and the Moscow region to take part in a school programming championship. The championship is called Coder-Strike 2014. The championship will be held based on Codeforces.

Goals

We aim to support talented high school children, help to form the community of programming enthusiasts, develop future IT professionals. The modern industry offers scientific challenges that cannot be solved without profound knowledge in the field of algorithms and data structures. We want to provide out participants with potential ways of development of with the opportunities that open in front of high qualified professionals.

Participants

You can participate if you study at 9-11th school year of one of a high school of Moscow or Moscow region. You should also be over 14 years old at the moment of registration to the championship. In order to become a participant of the championship, you need to register before you take part in the qualifying round at http://crocok.ru/championship/. You should submit the participant application form to take part in the championship officially.

Schedule

Stage Date / Time Participants
Registration March, 15 — April, 15 9-11th form of Moscow or Moscow region high school, who are over 14 at the moment of registration for the championship
Qualification Round April, 15 00:00:00 AM till 11:59:59 PM (24 hours)

You will need to solve at least one problem at any time during the 24-hour period of the round to pass it.
All the participants who registered for the championship
Round 1 April, 18 8:00:00 PM till 9:59:59 PM (2 hours) The participants who solved at least one problem in the qualification
Round 2 April, 20 11:00:00 AM till 12:59:59 PM (2 hours) The top 200 participants of the Round 1
Finals April. 22 (time will be specified later) The top 25 participants of the Round 2

The qualification round will consist of 2-3 easy programming problems, your solutions will be checked during the round. The rounds 1-2 and the finals will be conducted by the traditional Codeforces rules, you can learn more about them by these links:

Championship Finals

The championship finals will take place on April, 22 in the CROC company office on 5, Volochayevskaya street. The finalists will have an excursion along the company office an meet the leading specialists of CROC and the Ministry of Defence of Russian Federation. The time of the finals will be specified later.

The award ceremony will be on May, 20-23 on the exhibition by the Ministry of Defense called 'Complex Safety'.

Prizes

Prizes

All the participants who make it to the finals get souvenirs from the CROC company and the Ministry of Defense of Russian Federation.

Participation Out-of-Competition

All the willing users can participate in the championship out of competition. In this case the application form is not required. The sorting rounds and the finals will be Codeforces rating rounds.

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Announcement of Coder-Strike 2014 - Finals
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By gridnevvvit, 11 years ago, translation, In English

Soon (on March 16, 19:30 MSK) you are lucky to participate in Codeforces Round #236 for both divisions.

Problems have been prepared by me. It’s my first round for both divisions and I hope not last. I want to thank Gerald Agapov (Gerald) for help in preparation of this round, Ilya Los (IlyaLos) and Ignatyev Alexander (aiMR) for testing of problems, Mary Belova(Delinur) for translating the problems, Michael Mirzayanov (MikeMirzayanov) for marvelous Codeforces and Polygon systems.

UPD: Scoring system:

Div. 2: 500 — 1000 — 1500 — 2000 — 2500

Div. 1: 500 — 1000 — 1500 — 1500 — 2000

UPD:

Contest finished, congratulation for winners!

Div.2 :

  1. vladb
  2. iceiceice
  3. LoneFox
  4. ofpsxx
  5. adsz

Div. 1:

UPD:

Editorial.

UPD:

Round Statistics from DmitriyH.

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By EG0R, 11 years ago, translation, In English

Hello everyone!

Codeforces Round #235 (Div. 2) will take place on March 10th at 19:30 MSK.

This is my first Codeforces round and I hope not the last one.

I'd like to thank Gerald Agapov (Gerald), Roman Rubanenko (Rubanenko), Sergey Oryshych (Oryshych) for helping me to prepare round, and Mariya Belova for translation of all problem statements into English.

Scoring: 500-1000-1500-2000-2500

GL & HF!

Top five:

  1. UESTC_XHXJ

  2. GoodByeAhu

  3. OrzSKYDEC

  4. simonlindholm

  5. angelyue

Congratulations of participant hoanglmdiv2, who solved the problem E.

Unfortunately, my fault, in the round hit the problem that was previously used on another competition. Since it does not comply Codeforces, problem E will be deleted.

English tutorial

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By Berezin, 11 years ago, translation, In English

Hi! Soon Codeforces Round #234 (Div. 2) will take place, i am the author, Dmytro Berezin :)

Thanks to Gerald Agapov (Gerald) for the help in round preparation, Maria Belova (Delinur) for tasks translations, Mike Mirzayanov (MikeMirzayanov) for perfect system, and Sergii Nagin (Sereja) for his agreement (to share his evening with me) to help in testing.

Distribution will be announced as soon as found :) Standard :)

Good luck!

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By MikeMirzayanov, 11 years ago, translation, In English

On 02.03.14 there was a serious technical failure: Codeforces and related infrastructure hard drives have been corrupted. Unfortunately, it turned out that in contrast to all other components, the Codeforces database was not replicated properly. Polygon and Gym files were not injured. However, the Codeforces data has been significantly damaged.

We've rolled back the system to the state on February 7. It will remove 22 days of Codeforces life. Immediate efforts will be directed at the total exclusion of such situations. This is a very serious loss for me personally, which I can only blame myself.

Many thanks for all of you who supported us on a temporary Codeforces page. You helped much to find motivation in this difficult situation.

Currently the Gym is disabled. It will be opened back soon. We will return official contests and gym trainings with problems (but not results).

Data to be recovered:

  • official contests with problems (but without results);
  • public trainings in Gym;
  • non-public trainings in Gym, but we do not know their owners — write me if you've prepared non-public training in Gym (not a mashup).

Sorry again for the inconvenience.

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