998kover's blog

IZhO 2022
By 998kover, history, 3 years ago, In English

We hope that you enjoyed the contest.

Let's discuss the problems.

preliminary ranklist

upsolving

draft editorial

UPD We are grateful to MikeMirzayanov for the opportunity to host the contest on Codeforces.

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Comments Comments (10)
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3 years ago, # |
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It seems there are few participants whose results divided into 2 lines in ranklist

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    3 years ago, # ^ |
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    It looks like they used different accounts on different days. This will be corrected in the official results.

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3 years ago, # |
  Vote: I like it +9 Vote: I do not like it

nice contest, me and oleh1421 have enjoyed it)) how many participants will get gold medal?

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3 years ago, # |
  Vote: I like it +12 Vote: I do not like it

Will the test cases be published too?

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3 years ago, # |
  Vote: I like it +36 Vote: I do not like it

How to solve task E (Challenges of urban planning) with centroid decomposition? I don't quite understand the idea of the editorial :(

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3 years ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

What do you think how medals will be distributed?

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3 years ago, # |
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Observe that if al < ar and dpl,r = true than al < al+1 < .. < ar−1 < ar. Hence there are only one m such that am = al+ar 2 . Find it using two pointers or binary search. al > ar similar.

I didnt understand this part, can someone expain it?

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3 years ago, # |
← Rev. 2   Vote: I like it +4 Vote: I do not like it

Problem B. Zhylan.io, It seems tutorial contains an error, you need to look for the maximum value a_i — pref_i-1 to check answer, not the minimal(subtask 3 and 4)

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3 years ago, # |
  Vote: I like it +16 Vote: I do not like it

998kover, will be test cases and jury solutions added?

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23 months ago, # |
  Vote: I like it +13 Vote: I do not like it

Is there any good explanations of IZHO 2022 problem's solution.

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