skittles1412's blog

By skittles1412, history, 6 weeks ago, In English

Today when I was looking at my in contest submissions, I noticed that my D submission passed system tests in 639 ms. However, I remembered that it passed pretests in 872 ms 96579469. I checked my terminal history (I use cf tool for submitting) and it turns out my memory was correct.

I then decided to try and resubmit my in contest submission that had TLE'd 96576806. To my surprise, it AC'd with 842 ms 96606564!

Now, 200 ms difference and AC vs TLE is quite large. Is there a reason behind this, and could this be related to the queue at the beginning of the contest?

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6 weeks ago, # |
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I noticed the same thing in D today. It was 200ms faster during system tests

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    6 weeks ago, # ^ |
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    But I guess it is explainable by the fact that pretests contained "worse" input and system tests don't rerun them?

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      6 weeks ago, # ^ |
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      No I remember in Global 11 that 300iq's solution TLEd systests on the same test where it passed pretests. (problem G)

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      6 weeks ago, # ^ |
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      No. System tests include pretests. This can be manually verified by comparing the tests in my TLE submission and my AC submission.

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6 weeks ago, # |
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Same happened to my solution of D. Pretests passed at 840ms, I was worried about TLE. Turns out it passed system tests at some 623ms

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6 weeks ago, # |
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Yup, I guess testing was slower due to server load. I had a submission that got TLE on pretest 7 during contest, resubmitted it now and it got AC 5/5 times now. Maybe bad luck and it fails 1/10 times even with retrying, but test 5 runs considerably fastest (600-800ms) now compared to 900+ ms during contest.

In contest TLE — 96569792

Out of contest ACs — 96608464 96608563 96608567 96608572 96608576

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    6 weeks ago, # ^ |
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    Bad luck is almost never the case though. CF runs TLE testcases multiple times, so that doesn't seem to be the reason.