Challenge24 finals are finally over, and as usual, I hurry to share my impressions about them. The impressions are sponsored by team Progopedia (Andrii Maksay a.k.a. maksay, Sergii Dymchenko a.k.a. kit1980 and me). Such things are the best to write immediately after the contest, while the emotions still invade you. Of course, one can start writing them while still in the competition (and last year I did so — I was pretty useless at night anyways), but this year we felt alert and fought for the points till the last minutes of the contest, so the blog post was postponed.

The main part of Challenge 24 took a bit less than 48 hours: registration and optional sightseeing on Friday, the round itself from Saturday morning to Sunday morning, and winners announcement and closing ceremony (for the toughest contestants who don't really need all that sleep) on Sunday noon.

**UPD1: ABBYY Cup 2.0 is completed! **

UPD: Editorials here. They will be updated again :)

Hey, everyone!

We remind you that today at 16 PM the first division of ABBYY Cup 2.0 starts!

This contest is rather hard to be solved completely and it is aimed at the first division Codeforces participants!

Don’t forget to register for the contest!

The duration of the contest is 5 hours. You should solve six problems (one of those is heuristic). The tests are split into three categories (easy, moderate, difficult), they are worth 20, 30 and 50 points, respectively. Only fully passing a group of tests is counted. When contestants win the same number of points, the penalty time is counted by the ACM rules. Fully solving some group of tests is counted as submitting an ACM-problem and will determine the penalty time you get. The first division (hard) contest will be a rated event for any participant despite of the participant rating and type of participation.

We hope you’ll enjoy the contest! Good luck : )

Croc Champ 2012 - Final

Final Update: Congratulations to the prize winners!

• First place: neex.emil — 100000 rubles
• Runner Up: Dmitry_Egorov — Apple MacBook Pro 15
• 2nd Runner Up: vepifanov — Apple MacBook Pro 13

Videos for the onsite round (posted by ivan.popelyshev): 1 2 3 4 5 6

Congratulations to the winners of the mixed group (onsite & offsite)!
ivan.metelsky
YuukaKazami
neex.emil

rng_58 deserves honorable mention for the only competitor to correctly submit both D and E :)

Editorial.

Hello Codeforces!

I am glad to welcome you — both onsite and out-of-competition competitors — to the final round of Open Moscow Programming Championship By CROC. I am the writer of this round — Gerald, ivan.popelyshev and Delinur helped me in the preparation of the problems. This is my second round in Codeforces, so far, thanks to the Codeforces team and MikeMirzayanov for giving me this opportunity again!

Please note that this round is held in conjunction with its onsite counterpart, so its starting time may be delayed. Also, since MikeMirzayanov is very busy with the onsite contest at the moment to decrease the load (to avoid any disaster for the onsite competition), I apologize that you may not receive any email reminder about this match.

I've taken feedbacks from my last match into account, so the pretests will be fairly strong. The match should be more interesting for you if you decide to try and solve as many problem as possible, instead of stopping and hacking other codes early in the match :)

The rules below are copied-modified from Ripatti's post:

Competition will happen by usual rules of Codeforces, with hacks and score falling in process of time. The three championship winners will be awarded valuable prizes:

• 100000 rubles for the first place
• Apple MacBook Pro 15 for the second place
• Apple MacBook Pro 13 for the third place

Please remember that the round will be rated only for onsite participants and Division 1 contestants, since the problemset may be more tricky than usual (or it may not be :) ). Division 2 coders can participate, but it will not be rated for them.

There will be five problems ordered by approximately increasing complexity. The scores will be 500-1000-1500-2000-2500. Don’t forget that during contest your solutions will be tested on a small set of pretests. Testing on full testset will be after end of the round. Pretests can don’t cover all cases of input data, so you should test your solutions very carefully.

It is strictly forbidden to publish statements/solutions of the problems before round will be end. Also you shouldn’t to talk about problems, discuss some things about possible solutions of them. Let’s be honest! You can discuss problems after the end of round.

Good luck everyone! I will be watching :)

Good Day, Codeforces!

Remember, that at 17:15 the final of the Open Moscow Programming Championship By CROC will start.

As usual anyone wishing to participate in this round can compete in it out of competition. But as this competition is quite complex, it will be rated only for participants from Div.1.

Note that this competition is closely connected with onsite competition in Moscow. So the starting time can be shifted. Watch closely for changes in the schedule.

Welcome friends)

We are glad to introduce you regular Codeforces round #117 for Div.2 participants. Everyone can traditionally participate in it.

Problems are prepared by command of authors: Pavel Kholkin (HolkinPV), Ivan Fefer (Fefer_Ivan), Nikolay Kuznetsov (NALP) and Gerald Agapov (Gerald). Thanks to Michael Mirzayanov (MikeMirzayanov) for Codeforces system and Mary Belova (Delinur) for translating problems.

And again score distribution will be dynamic) More information you can find here.

Note that all problems today will be given in random order.

Some Div.1 participants register for the contest before settings of registration were changed. Before the round it will be fixed and they will participate out of competition.

We hope that todays round would be succesful and everyone enjoys it. We wish you good luck and high rating!

UPD: the statement for problem 182E - Wooden Fence was formulated incorrect, correct variant of the statement will be soon, we apologize to the participants.

UPD2: the contest is declared unrated.

Hello!

Today it will be good old ACM-ICPC round. Yes, it will be the rated event for the second division, and the participants of the first division will be able to participate out of competition.

Problems have been prepared by Nerevar, natalia, MikeMirzayanov and Edvard, and Delinur translated all the problems. Thanks!

Good luck!

UPD: Ratings will be updated later. Sorry for delay.

Hey everyone!

Dear all, we remind you that today at 18 PM the second division of ABBYY Cup 2.0 starts!

There will be a special problem from Codeforces as a present for participants!

The duration of the contest is the same. You should solve seven problems in four hours. The tests are split into two categories (easy and difficult), they are worth 30 and 70 points, respectively. Only fully passing a group of tests is counted. When contestants win the same number of points, the penalty time is counted by the ACM rules. Fully solving some group of tests is counted as submitting an ACM-problem and will determine the penalty time you get. As MikeMirzayanov commented:

The second division (easy) contest will be a rated event for Div. 2 Codeforces users, so it will be rated for official participants and those unofficials who is from the Codeforces Div. 2.

These contests are officially available to those who is included in the Codeforces’ second division. The Codeforces’ first division users can take part in the second division out of competition.

Good luck!

Hello everyone!

Today is the second round of the Open Moscow Programming Championship By CROC will be. Start is planned at 19:00.

Competition will happen by usual rules of Codeforces, with hacks and score falling in process of time. All contestants who passed score no less than contectant of the 300-th place in the Round 1, can participate in the Round 2. Every other contestants can patricipate the Round 2 out of competition. Specially for contestants of the second division we prepared more easy unofficial problemset. The official problemset and the unnoficial one have some common tasks.

Round will be rated for all participants.

Some number of problems are waiting you. They are roughly ordered by the increasing complexity. Score distribution is standard for both divisions (500-1000-1500-2000-2500). Don't forget that during contest your solutions will be tested on a small set of pretests. Testing on full testset will be after end of the round. Pretests can don't cover all cases of input data, so you should test your solutions very carefully.

It is strictly forbidden to publish statements/solutions of the problems before round will be end. Also you shouldn't to talk about problems, discuss some things about possible solutions of them. Let's be honest! You can discuss problems after the end of round.

Top 50 contestant will be allowed to the Final Round. Also all contestant with score not less than score of the 50-th contestant will be passed.

The round was prepared by Ripatti, havaliza, Gerald, RAD, MikeMirzayanov, Delinur.

Good luck for all!

UPD. We remind that the final of the Open Championship of Moscow and Moscow Region Programming (CROC) take place on April 27 in the office of the CROC. Note that CROC does not pay for the road and residence of the finalists. All participants must arrive at the final in the office of the CROC (Moscow) in the morning on April 27.

After the competition all participants will be provided to fill the form on the ability to participate in the finals of the competition. The first 50 participants on the results of the competition, which will confirm their participation in the finals, will be invited to final competition. You can confirm participation in the finals during the day after the end of Round 2.

It is recommended to fill the form, regardless of your results in Round 2, as large number of participants can reject the participation in the final.

Dear all!

Do you already have any plans for the nearest saturday evenings?

If you want to spend it with ABBYY Cup click here to register! There are special checkboxes for pupils and graduates to take part in out of contest.

If want to take part in contest, registration is obligatory. If you are not, it's free.

As MikeMirzayanov commented:

The second division (easy) contest will be a rated event for Div. 2 Codeforces users, so it will be rated for official participants and whose unofficials who is from the Codeforces Div. 2.

The first division (hard) contest will be a rated event for any participant despite of the participant rating and type of participation.

Hello everyone!

I am glad to invite You to take part in round #115 which is rated for participants of both divisions. As in last year, in this round You will help gamer Vasya to find himself in the virtual world of computer games: brag to his friends about his achievements, determine who is a "noob" and who is a "hardcore" player, destroy the Main Evil, play several rounds of the Plane of Tanks and get rid of the crowd of very bad gnomes. Generally, get a lot of fun!

The round authors are Gerald Agapov (Gerald), Evgeny Lazarev (undef) and Alexey Shmelev (ashmelev). Vladislav Epifanov (vepifanov) and Maria Belova (Delinur) helped us with the round preparation.

In this round You will be given 6 problems, instead of usual 5, also the round duration is increased from 2 to 3 hours.

P.S. Probably You have noticed the contest with strange name "RazMERiq 2012 (Private Contest)". Onsite contest based on Codeforces platform (big thanks to Mike Mirzayanov for the provided opportunity) and problems of this round will be held simultaneously in Nizhny Novgorod. Please, do not register on that contest:)

UPD: dynamic problem max scores will be used in this round.

UPD2: because of a mistake in problem 175B - Plane of Tanks: Pro and changed problem statement, please write a message to Gerald if your solution failed on test 4 because of the problem statement change. Please, specify the submit id in the message.

UPD3: Editorial.