mblazev's blog

By mblazev, history, 5 weeks ago, In English,

So i used Arpa's bigint for today's C: https://codeforces.com/blog/entry/22566 and got skipped. Isn't it allowed to use code written before contest? What's going on here fcspartakm?

 
 
 
 
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5 weeks ago, # |
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Pinging everyone else to get attention BledDest Vovuh MikeMirzayanov.

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5 weeks ago, # |
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s̶h̶o̶u̶l̶d̶'̶v̶e̶ ̶j̶u̶s̶t̶ ̶u̶s̶e̶d̶ ̶p̶y̶t̶h̶o̶n̶

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5 weeks ago, # |
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this might help link. feelsbadman T_T

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    5 weeks ago, # ^ |
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    Well yeah, I would guess contest authors are aware of codeforces rules...

    the code was written and published/distributed before the start of the round,

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5 weeks ago, # |
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Sure it is a false positive plagiarism detection issue. It happens rarely. But did you read the comment from the system? It gives you a standard way to resolve such issues. No need to write posts like this. UPD: Sorry, I don't know why you didn't receive a message about the violation. I'll investigate it.

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4 weeks ago, # |
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Hi went through your solution. I am unable to understand couple of things.
What is the purpose of substracting and adding 1 for upper k or lower k?
Thanks

bigint df(bigint a, bigint b)
{
    if (b < 0) a = -a, b = -b;
    return a / b &mdash; (a % b < 0);
}

bigint dc(bigint a, bigint b)
{
    if (b < 0) a = -a, b = -b;
    return a / b + (a % b > 0);
}
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    4 weeks ago, # ^ |
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    Those are div floor and div ceil functions and they do exactly that. The inequalities for k come from requirement that solution is greater or equal to zero.