CodeForces Beta Round #15
By Shtrix, 14 years ago, translation, In English

Greetings, CodeForces users. CodeForces Beta Round #15 will be held today, 29th of May at 19:00 MSK. My name is Roman Iedmeksyi and I am lucky to introduce this problem set.

I would like to thank Dmitry Matov, Julia Satushina and Mike Mirzayanov for well-coordinated work on this match. Also I would like to mention the contribution of Yaroslav Tverdokhlib in problems testing.

Some information about me:       

I am a student of Kyiv National Taras Shevchenko University. I started programming at school. As my first achievement I had taken third place in Ukrainian Olympiad in Informatics. Next year I’ve worked harder and was qualified to IOI 2009 selection. Unfortunately I had not enough experience to pass.

In this contest I wish you good luck and high results.

UPD contest extended by 15 minutes

UPD Codeforces team apologizes that during today's round the server was regularly unavailable due to different technical reasons. We will try to do our best to avoid similar situations on the upcoming contests. Our apologies for some mistakes in the statements. Because of these reasons today's competition results will not affect your rating.

Looking forward to seeing you at Codeforces Beta Round 16.

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Announcement of Codeforces Beta Round 15
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Saratov Summer School "Sazanka 2010"
By MikeMirzayanov, 14 years ago, translation, In English

The first information letter


General information


From 2nd to 12th August 2010 Saratov State University runs an international student summer school in computer programming. Teams of three people and individual participants are invited to take part in it.

The school will take place in a picturesque place at one of Saratov resort centers on the Volga bank. The participants will be provided comfortable rooms for 2-4 people and meals three times a day. The resort center owns a beach and sport grounds.

The school curriculum includes lectures by Saratov state university coaches, joint trainings, problems tutorials and topical workshops. The curriculum is designed for younger university students who aspire to achieve high results at programming competitions.

The fees are 15000 RUR (~ 500 USD) for a person. Moreover, each team or an individual participant should bring a laptop with the support of WI-FI.

All interested participants and teams should register at http://acm.sgu.ru/sazanka-2010/ till 10th June 2010. Don't postpone the registration, as the number of participants we can take is limited.

You can get additional information by e-mail mirzayanovmr[symbol-at]gmail.com. As since the official language of the school is Russian, the registration requires knowledge of Russian. Also it is recommended to view this page in Russian.

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Codeforces Beta Round #14 (Div. 2)
By MikeMirzayanov, 14 years ago, translation, In English
Today's round is not quite usual. The participants of the first division can register on it and to participate out of competition. This round will be some alpha-testing for this functionality, but for the next div. 2 round you can expect a stable version. 

This round prepared for you by: homo_sapiens, Julia, Nerevar, KudryashovIA and me. 

I want a high-ranking 
MikeMirzayanov

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Codeforces Beta Round #13 editorial
By KADR, 14 years ago, translation, In English

Let me introduce an editorial to Codeforces Beta Round #13. If you have any questions or propositions - feel free to post them in the comments.


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Codeforces Beta Round #13
By KADR, 14 years ago, translation, In English
Welcome all to Codeforces Beta Round #13, which will be held on Thursday, 6th of May at 18:00 MSK. I am an author of the problems.
I would like to thank Mike Mirzayanov who made this contest possible, Roman Iedemskyi and Andriy Maksay for helping to test authors solutions and Dmitry Matov for the translation of problem statements into English. Hope you will like the problems.

I hope that number 13 would be lucky for you!


UPD: Congratulations to Ivan Metelsky who became the winner, having solved all 5 tasks!
You can view the tasks here.
You can view the results here.

UPD2: I've added an editorial.

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Announcement of Codeforces Beta Round 13
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Codeforces Beta Round #12 (Div. 2)
By MikeMirzayanov, 15 years ago, In English
Hello again. I hope nobody has forgotten to register?

In this contest we will try alpha of our chat - if something goes wrong, we turn it off: please do not panic:)

Links:
Problemsetters: Дмитрий Матов и Игорь Кудряшов. Thank them for their contributions.

I wish you to advance to the first division.
Mike Mirzayanov.

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Codeforces Beta Round #11
By meret, 15 years ago, In English
Let me warmly welcome you to Codeforces Beta Round #11. I am the main problemsetter for this contest. I hope you'll have fun solving the prepared tasks :-)

Thanks to Mike Mirzayanov for making this possible and to Ania Piekarska for testing the problems.

Good luck,
Jakub Pachocki

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Announcement of Codeforces Beta Round 11
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Codeforces Beta Round #10
By Nerevar, 15 years ago, translation, In English
Codeforces Beta Round #10 took place on Thursday, 15th of April at 19:45 MSK. This time I am the author of the problems. I would like to thank the creator of the Codeforces Mike Mirzayanov for correcting the statements and Julia Satushina for the excellent translation problem statements into the English.

I want to apologize for the problem D. There was a bug in model solution. Moreover, this problem may not be solvable in polynomial time even with such constraints on the number's size. We will investigate it. I hope nobody will feel offended in any case.

UPD: Now I am pretty sure that my model solution for the problem D was completely wrong. I want to apologize for it again. There will be no rejudge of the solutions accepted during the contest. The statement will be changed so that it will ask to find the LCIS of the two sequences. This problem definitely has a solution.

UPD: Problem D was changed as I promised.

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Announcement of Codeforces Beta Round 10
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Codeforces Beta Round #9 tutorial
By slycelote, 15 years ago, In English

A. Die Roll

If the maximum of Yakko's and Wakko's points is a, then Dot will win, if she has not less than a points. So the probability of her win is (6 - (a-1)) / 6. Since there are only 6 values for a, you can simply hardcode the answers.

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Codeforces Beta Round #9
By Alex_KPR, 15 years ago, translation, In English

Hi, everybody, and welcome to the Codeforces Beta Round #9!

I'm its author. :) I've tried to make problems easy to read and funny. I’d like to say thank you to Mike Mirzayanov (for choosing problems for the contest and everything he’s done to organize it), to Igor Kudryashov (for checking author's solutions and making test generators), to Dima Matov (for correcting everything :)) and, of course to Julia Satushina (for excellent translations of the problems’ legends).

I'd like to remind you that if you have any questions on the problems, the best way to ask them is to use the web interface on the problems page.

I believe that the contest will be interesting to you, dear participants! I’m looking forward to seeing your suggestions here.

Good luck!

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