MikeMirzayanov's blog

2014-2015 CT S02E03: Codeforces Trainings Season 2 Episode 3
By MikeMirzayanov, 10 years ago, translation, In English

Welcome to 2014-2015 CT S02E03: Codeforces Trainings Season 2 Episode 3 (NCPC 2008 + USACO DEC07 + GCJ 2008 Qual). The training duration is 4.30 hours. It is opened for teams as well as for individual participants. After the end you may use the practice mode to complete problem solving. Also it will be availible as a virtual contest for whose of you who can't take part today. Please, do not cheat. Only fair play!

It is possible that the problems will be too easy for some participants, it is possible that we will add some problems.

Good luck!

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10 years ago, # |
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Where I can rigester it?

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10 years ago, # |
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Can someone who solved D explain why it is brute-forceable? Thanks..

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10 years ago, # |
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Hi , I am getting TLE in problem I ( Introspective Caching ) . This is my code : http://ideone.com/UThJix I can't understand which part of my code is costly. Can someone identify the part of my code which leads to TLE .

Edit : Found my mistake .. :D

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10 years ago, # |
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Can someone provide solution to K?

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    10 years ago, # ^ |
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    Brute-forse with O(n^2) complexity:)

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      10 years ago, # ^ |
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      Wow. I thought it'd be too much. Thanks, got AC. Now I can see that it could be done with suffix array...

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        10 years ago, # ^ |
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        We also thought it'd be too much:) But something clicked in my head at the last moment:) And we got +7)

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      10 years ago, # ^ |
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      Could you explane this in more detail?

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10 years ago, # |
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Missed the contest due to the late announcement :(

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10 years ago, # |
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So many participants who solved B, but I have no single idea how to do it. Wouldn't someone explain it to me? Especially why we can put one file in 0 bits.

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    10 years ago, # ^ |
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    In this problem, you need to check: Is it possible to file tags so that the length of the label was no longer a B and all the labels were different. That is, the answer is yes, if 2 ^ (b + 1) -1> = n

    Sorry for bad english. Google translate =)

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10 years ago, # |
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Hey everyone,I am new to codeforces gym.please tell me whether we get any editorials after contest or not and since other's solutions are not visible, how to understand solution of problems I couldn't solve .

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    10 years ago, # ^ |
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    There are no official editorials but you can discuss about the problems here and share your approach. You can't see others solutions as they become visible only when you are able to solve that problem.

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10 years ago, # |
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What is the idea behind Problem A ( Aspen Avenue ) ? I think it involves DP but how to represent DP state in this case.

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10 years ago, # |
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how to solve C Code Theft ??

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10 years ago, # |
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Problem K's judge seems to be behaving randomly. Is there some undefined behavior in my code?

Submission 1: http://mirror.codeforces.com/gym/100494/submission/8183454

Submission 2: http://mirror.codeforces.com/gym/100494/submission/8183446

Can someone figure this out?

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    10 years ago, # ^ |
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    You're using scanf and streams to input data.

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      10 years ago, # ^ |
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      That's just one version. I tried multiple combinations. Plus, I think they can be used together.

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10 years ago, # |
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I found the official website for ncpc 2008, which has input/output and solutions sketches, and judge solutions. Every problem except the last two seems to be from ncpc 2008. The solution sketch is not too detailed, but I thought I'd share and I hope this helps.

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