darkkcyan's blog

By darkkcyan, history, 21 month(s) ago, In English

Hello again Codeforces!

We are glad to invite you to take part in mirror round of the second round of VNOI Cup, which will take place at 13:00 UTC, on this Saturday, 25th June, and it is hosted on our builtin platform — VNOJ!

round2-poster

If you are Vietnamese and qualified according to these rules mentioned on this post, please consider taking part in the official round!

VNOI Cup is a Competitive Programming competition held by VNOI (Vietnam Olympiads in Informatics community), which is a non-profit organization, by Vietnamese competitive programmers, for Vietnamese competitive programmers. Our aim is to support the growth of competitive programming in Vietnam, and we hope that this competition is one of the things that follows this aim!

There are 3 elimination rounds and a Final round in this competition. Last week, we already held the the first round, with a lot of participants! Thank you so much for participating!. In this elimination round, there will also be 5 problems to solve in a duration of $$$150$$$ minutes. The problem statements for the mirror rounds will be in English. We have worked our best to make sure that the round have a good range of difficulties, so we welcome everybody to join this mirror round!

Remember that the round will take place at 13:00 UTC, on this Saturday, 25th June, and you can take part in the round via this link!

Other rounds info:

Hope you enjoy the rounds and thank you for participating! <3

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21 month(s) ago, # |
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Auto comment: topic has been updated by darkkcyan (previous revision, new revision, compare).

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21 month(s) ago, # |
  Vote: I like it +31 Vote: I do not like it

Clashes with CF Global Round.

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    21 month(s) ago, # ^ |
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    yes @Vietnamese Scientific Committee, please move your stupid olympiad it clashes with codeforces round global round how are people supposed to go to codeforces global if your olympiad is organised int the same time please move it thanks

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21 month(s) ago, # |
  Vote: I like it +10 Vote: I do not like it

TL too tight for problem D.

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    21 month(s) ago, # ^ |
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    Hi. Sorry for inconvenience :(.

    On Polygon we have set the TL to 3s, since the model solution ran in 1.5s. But when importing the problem on Polygon, because of hardware's differences, the model solution ran in 1.8s. But I did not notice that, so the problem's TL remains the same.

    For now we don't intend to change the TL, since it would be disadvantage to the official participants. Also the problem is still solvable under the TL.

    Again, we are very sorry for the inconvenience! :(

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      21 month(s) ago, # ^ |
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      Thank you for reply. Yes the problem is still solvable (I think it would be bad if a contest had an unsolvable problem). Makes sense not to change anything about problem now, since the contest is already done. I just dont see why not to set limits lower. I really doubt any sqrt decomposition would pass if (n , q) <= 5e5, intead of 1e6. Were you trying to cut log^2(n) solutions ?

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        21 month(s) ago, # ^ |
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        Hmm, the only thing we were trying to cut of is just sqrt decomposition. We also tried to cut of Mo algorithm with Hilbert curve order (which is very tricky).

        But we have not thought of any log^2 solution, so that was not our intention.

        Anyway thanks for your feedback! We will try to adjust the future problem to fit the constraints better.