For technical reasons, some programming languages (Kotlin, C #) will not be available during round 877. ×

By ashmelev, 7 years ago, translation, In English,
Good afternoon!

Authors of the today's contest are Evgeny Lazarev (Nizhny Novgorod STU) and me (Alexey Shmelev, Nizhny Novgorod SU)

Today you will help a boy Vasya find himself in the world of computer games.

Please note, that the round will be held in unusual format - 6 problems with costs 500, 1000, 1000, 1500, 1500 and 2000 points.
 

The round duration is increased to 2 hours and 30 minutes.


We say thanks to Marya Belova for statements translations, Artem Rakhov and Alexander Kouprin for help in contest preparation, writing alternative solutions and preparing of intricate tests.

Good luck and successful submission!

UPD: We apologize for inaccuracy in problem E and incorrect answers to several contestant clarifications.

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Announcement of Codeforces Beta Round #66
 
 
 
 
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By MaximShipko, 7 years ago, translation, In English,

Hello!

As many of you have noticed we have new features on Codeforces. The tab “Friends” has appeared on the user ratings page. But it is only the first of improvements made. Now you can view a list of friends on problemset standings, contest registrants and contribution standings pages. Because of increasing popularity of Codeforces the pagination has been added to the rating page.

But that's not all. In order to classify problems, it was decided to introduce the ability to add tags to them. Search by tags is not implemented yet, but administrators and users with high (your color should be at least blue) rating can add tags right now. To do this, simply open the desired problem and add tags in the sidebar form.

As you can see, the project development is actively underway. We would like to hear from you new constructive suggestions. 


Updated:

In the near future will be implemented a compact view of tags in the problemset and a setting to show/hide tags.


Maxim Shipko, Codeforces Team

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By MikeMirzayanov, 7 years ago, translation, In English,

The coding phase has been finished. Please wait for the final testing and results.

Good day everybody.

Everything written below is not a April Fool's joke. Though it is also a funny occasion :)

We are glad to announce a new experimental contest on Codeforces, "Problem Parser Contest".

Have you ever made training sessions, using the previous contests' archives? Have you downloaded from the Internet contest archives to test for your solutions locally? If the answer is 'yes', then you couldn't help noticing that each organizer insists upon inventing his own way (format) to distribute problems. Yes, it is true!

I've prepared and organized a huge number of trainings based on the previous contests. It is often rather a monotonous task; one often has to write some scripts that rename the input/output files of the problem into the standard form. In archives they are called very differently: they can be river.in.1, river.out.1, river.in.2, river.out.2, etc. In another problem they can be tests/1.dat, tests/1.ans, tests/2.dat, tests/2.ans etc.

At some point I got fed up with it and wrote a script that told the patterns of paths to the test files, using some heuristics and the regularity I'd noticed. The script worked well, but it wasn't perfect.

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By Ripatti, 7 years ago, translation, In English,
Hello everyone!

I am an author of today problemset. It is my second round on Codeforces. I hope you will like this round like my first one:)

Good luck!

UPD
Winner is unicef.
Editorial.

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By MikeMirzayanov, 7 years ago, translation, In English,

Unusual tournament Manthan 2011 showed the weaknesses of the current rating formulas. After the end of contest the winner of the competition tourist has expected rating change equal to "-1":)

This has arisen due to reduction of the calculated changes in such a way, that total sum is equal to 0. That is, Gennady was in some pros before such changes, but as the sum of all the changes turned out to be positive, then all the ratings were a little reduced. As a quick dirty hack in the round I turned off this feature, leading to a one-time inflation. Even a small mistake: I noticed that participants in the second division get too many points after a good performance on "Div. 2 Only" rounds.

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By Connector, 7 years ago, translation, In English,
I'm glad to see you on Codeforces Beta Round # 64.

Today I am the author of the tasks. I'm a student of Tyumen State University.

I want to thank all those who helped me to prepare the round: Nikita Durynin (Austeritas) for the pair ideas for the tasks, Dmitry Bochkarev (Walrus) and Chernenkov Alexey (Laise) for the testing, Artem Rakhov (RAD) for coordinating the activities, Maria Belova for translating and Mike Mirzayanov (MikeMirzayanov) for a great system.

Today you will visit the Walrusland and help the common citizens and government to solve their problems.

Good luck for everybody, let the best man win!

Winner is Petr. Congratulations!

Analysis

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Announcement of Codeforces Beta Round #64
 
 
 
 
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By map, 7 years ago, translation, In English,

Hello!

Today I am the author of all tasks. At the contest you will be asked to help students from Chelyabinsk in solving their non-trivial problems.

I want to thank all those who helped me to prepare the round: Anton Garder for his invaluable assistance in the preparation of sets of tasks, Demid Kucherenko for assistance in the preparation of conditions, Artem Rakhov for coordinating the activities and patience J, Maria Belova for translating and  Mike Mirzayanov for a great system.

 Good luck!

Winner - Solo

Analysis - http://codeforces.com/blog/entry/1571

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By A.K.Goharshady, 7 years ago, In English,

Hi all!

Unknown language round #1 was up, 21st of February and now we're going to hold yet another Unknown language round.

It will be the usual ACM-ICPC unrated contest , so there is no hacking! The only feature - you will be able to submit problems using the only one, not very popular language. What? It's a secret! And I expect you'll have to learn the language at the time of contest since the used language will be a secret until ~1 minute before the start of contest.

Problem setters of this round are Alireza FarhadiSaeed IlchiSajjad GhahramanpourZahra Rohanifar and Me. We are extremely grateful to Mike Mirzayanov and Artem Rakhov.

Number of problems will be more than usual and the problems concentrate on coding abilities rather than algorithmic view and problem solving techniques.

UPD:The contest is over

Congratulations to the top 3 winners who solved all problems:

Wrong

tomek

watashi


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Announcement of Unknown Language Round #2
 
 
 
 
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By maksay, 7 years ago, translation, In English,
Hi everybody!

Today authors are me and Roman Iedemskyi (Shtrix). Big thanks for help in preparing problems to our teammate Iaroslav Tverdohklib, Artem Rakhov, Maria Belova and Dmitry Matov.

Hope you will enjoy the contest!

UPD: Congratulations to winner rng_58!

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Announcement of Codeforces Beta Round #62
 
 
 
 
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By Tachyon, 7 years ago, In English,
CodeFest'11, the annual online international coding festival of Computer Engineering Society IT-BHU, presents Manthan - the algorithm intensive programming contest. The name Manthan or मंथन has been taken from the Hindi language and means Brainstorming. Google Logo CodeFest Logo

The contest aims to provide a platform for programmers round the globe to showcase their problem-solving and programming skills. Most problems of the event will be real life computing problems where coders will be required to prune existing standard algorithms to find the solution for the domain specific application of the algorithm.

We are proud to have Codeforces as our partner for Manthan 2011. The Contest will be hosted on Codeforces and will follow the rules similar to that of Codeforces Beta Round.

Google Sponsored event with Prizes worth 50,000 INR. Besides, Certificates to top 50 participants. 

You need to follow the registration procedure in order to be eligible for prizes.

Event Details:
  • The main event is scheduled on March 13 at 2200 Hrs IST (UTC+5:30)
  • Rules of contest similar to Codeforces Beta Rounds.
  • The Contest will be of 3 hours consisting of 5-6 problems.
  • Programing languages allowed: C, C++ , Pascal, Java, C#, Python, Ruby, PHP, F# and Haskell.
  • Open to all, students as well as professionals.
  • Declaration of Results on March 16 at 1800 Hrs IST.
Note: Contest duration has been reduced from 4 to 3 hours.

Visit the Manthan event page for further details of the contest.

Registration for the competition will occur automatically on the fact of your registration on the official CodeFest site. If you have been properly registered there, then your Codeforces handle should appear in the list on http://codefest.org.in/codeforces-handles.php, and registration for the contest will take place
automatically.

The contest duration changed to be 3 hours. Good luck!

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Announcement of Manthan 2011
 
 
 
 
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