fractal's blog

IZhO 2025
By fractal, history, 5 weeks ago, In English

The XXI International Zhautykov Olympiad(IZhO) took place from January 13 to January 17 in Astana, Kazakhstan.

The results can be found here: Results

Scoreboard with points for each task is available in GDrive.

Problems can be found here: Problems

Editorials will be published soon.

The tasks were authored and prepared by Temirlan, Aidos, bthero, sstrong, Mansur, DimmyT, Lokeo, dimachine, ArsenGotov, NaughtyMorzh, fractal.

We are looking forward to seeing you at IZhO 2026.

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5 weeks ago, # |
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Is there a scoreboard that shows the breakdown per problem?

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5 weeks ago, # |
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Why does the text of the results link say 2020

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5 weeks ago, # |
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Does anybody have an idea why is this happening? (Why not perfect result?)

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    5 weeks ago, # ^ |
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    Sorry, problem was incorrectly uploaded.

    All of the submissions for B are rejudged.

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5 weeks ago, # |
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Problem B's big test cases seem to be weak. To test the intended solution's correctness, I submitted it with O(N^2) implementation, it got 78 :)

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    4 weeks ago, # ^ |
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    Same for me. C also has problems — selecting the part with less vertices in the bipartite graph to be the "maximal matching" passes on the tests.

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      4 weeks ago, # ^ |
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      Wow, that is interesting. Also, congratz for the win!

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      4 weeks ago, # ^ |
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      The tests for problem C1 have been fixed in the gym. Does it still pass the tests or was it during the main contest? By the way, sorry for wweak tests during the contest(

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        4 weeks ago, # ^ |
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        I know people have passed them during competition, haven't tried out the gym's ones yet.

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        4 weeks ago, # ^ |
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        I tried, but doesn't seem to pass. Also, what's the full solution for C1? I found a O(N^5) solution with Kuhn, also tried Dinic with O(N^4.5), but didn't passed last two subtasks.

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          4 weeks ago, # ^ |
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          The editorial will be published soon, but roughly you need to notice two ideas:

          Draft of solution
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        3 weeks ago, # ^ |
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        The only 300 on the first day had both solutions for B and C wrong)

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5 weeks ago, # |
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libobil orz!!!

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5 weeks ago, # |
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when will editorials be posted?

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    5 weeks ago, # ^ |
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    We will publish editorials in a few days.

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4 weeks ago, # |
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why cant i see others solutions?

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4 weeks ago, # |
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for problem B is the solution:

Spoiler

If not please share your solution)

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3 days ago, # |
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editorial when?

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