radioegor146's blog

By radioegor146, 7 years ago, In English

Hello Codeforces!

Here is detailed overview of results of IZhO 2018:

There was 2 round each 5:00:00 long with 3 problems. The second round time was increased for 15 minutes because of some problems with one of tasks. IOI rules.

  • 137 participants took part in the competition
  • Highest result is 549 points and it was received by Roman Korobkov (romanasa)
  • The first five winners are:
    1. Roman Korobkov — Russia — romanasa
    2. Gainullin Ildar — Russia — 300iq
    3. Karneichyk Mark — Belarus — markysha
    4. Anoprenko Mikhail — Russia — manoprenko
    5. Kairly Nurlykhan — Kazakhstan — Nurlykhan


There is full table of results and submits:

Table of results and submits

But now it's time for statistics!

Scoring for each task:

1st day:

Tasks (English)

1st task (chessboard):



2nd task (plan):



3rd task (nicegift):



Overall



2nd day:

Tasks (English)

1st task (segments):



2nd task (sequence):



3rd task (treearray):



Overall



Results




Some time later (after official results) I will post raw data (with detailed timings and points of sent solutions) (json) about this competition! Just wait about 2-3 days.

Good luck everybody!

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7 years ago, # |
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Btw how to solve problem 4 (segments). I had a solution with two sqrt decompositions, but it couldn't fit in TL. Is there a solution without sqrt decomposition? Thanks in advance.

PS: The solution only uses binary searches and a persistent segnent tree (inside the sqrt buckets), so the constant shouldn't be large. I also made a couple of constant optimization.

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7 years ago, # |
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Will there be an analysis for all of these problems?

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7 years ago, # |
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Kairly Nurlykhan's handle is Nurlykhan.