Блог пользователя smokescreen

My first attempt at making a CONTEST.
Автор smokescreen, история, 6 лет назад, По-английски

Hello Codeforces!!

This was our first attempt at making a contest.

I and my friend, a_kk , we both made a contest for our college. There were a total of 6 problems(4 easy and 2 medium) and participants were given 2 hours to solve them.

The problems are interesting. All those who want to try them are invited. If you're an expert or less, then definitely, you'll learn something :)

Link to the contest : link

It would be lovely to have feedback from your guys!

Happy solving!!

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6 лет назад, # |
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How to solve "Jitu and strings" if the no of swaps was given to at most K. Where K could be in the order of length of the string?

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6 лет назад, # |
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I solved 4 problems in 2 hours:

  • "A. hmrockstar at bank" — O(n), linear maximum search. Code.
  • "B. haaby's dream job — Digital Cleaner" — O(sqrt(k)), mathematics, dividers, combinatorics. Code.
  • "C. KJ and street lights" — O(n sqrt(n)) — SQRT-decomposition + linear search for the maximal sequence of zeros. Code.
  • "D. Jitu and Strings" — O(n log(n)) — polynomial hashes + binary search. Code

After 2 hours solved:

  • "E. Arun sir and his girlfriend!" — O(n log(n) * WORD_WIDTH) — sort + implicit prefix tree + binary search. Code

Nice problems, thanks! Is the contest already complete and can I open the source code of solutions?

And your problem D does not contain an anti-hash test :((

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    6 лет назад, # ^ |
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    nice to hear that u liked the problems :)

    As it was our first contest we didn't knew the testcases were weak for polynomial hashes.We were lucky that no one made a submission using similar solution to yours :P. We will try to add a anti-hash test case though.

    The solutions have been made public.

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      6 лет назад, # ^ |
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      Will you publish editorial?

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        6 лет назад, # ^ |
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        Yes, I've published the editorial.

        The editorial consists of brief explanation of the approach to solve the problem. Still, I have made my solutions available for reference. If there is still something unclear, just do tell us. We'll be happy to help. :)

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          6 лет назад, # ^ |
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          I solved the problem "E. Arun sir and his girlfriend!" and added the code. I think that this is easier, than jury solution in editorial.

          Solution: sort + implicit prefix tree + binary search, O(n log(n) * WORD_WIDTH)

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6 лет назад, # |
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Nice problems. But can these problem be added in any vjudge contest? I tried, but vjudge couldn't crawl the problems. Any way to add in vjudge contest ?

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