Temirulan's blog

Codeforces contests problem evaluation format
By Temirulan, history, 4 years ago, In English

So far I thought that the number of lost points per minute is calculated by formula initial_cost / 250. According to this post I'm correct. But after some lookup into standings of last contest I found some contradictions:

  • Problem А (500 points): 1 point per minute
  • Problem B (750 points): 2 points per minute
  • Problem С (1000 points): ~2.67 points per minute
  • Problem D (1500 points): 4 points per minute
  • Problem E (2000 points): ~5.33 points per minute
  • Problem F (2500 points): ~6.67 points per minute
  • Problem G (3000 points): 8 points per minute
  • Problem H (3500 points): 9.33 points per minute
  • Problem I (4000 points): 10.67 points per minute

That definitely says that I was wrong. I'm not complaining about format or something else. Just want some explanation of exact formulas. Am I missed some new clarification on that thing MikeMirzayanov?

P.S: just seeking for explanation after no answer on comment. Constants was calculated from great performances of boboniu and maroonrk.

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4 years ago, # |
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It's usually scaled with the contest duration and that one was 3h instead of 2h.

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    4 years ago, # ^ |
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    Is exact formula totally clear for you? I thought number of decreasing points proportional to initial cost.

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4 years ago, # |
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To follow on to what Errichto said, the lost points seem to be inital_cost/375, as expected. This matches exactly with your empirical lost points measurements except for with Problem A, which might be due to rounding error as I assume boboniu and maroonrk solved A in only a couple minutes.

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4 years ago, # |
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Point loss per minute is (probably): $$$\frac{2P}{250D}$$$

  • $$$P$$$ is the initial point.
  • $$$D$$$ is the contest duration in hours at the beginning of the contest(i.e. doesn't change if the contest was extended during the round).
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    4 years ago, # ^ |
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    It seems you're right. But it can be justified only by CF stuff.

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