amiralisalimi's blog

Weird fast execution time on Codeforces
By amiralisalimi, history, 5 years ago, In English

I am facing a really weird fast execution time on Codeforces on submission 75468775. On test #6, the code runs for 1153 ms on Codeforces servers, but when I run it on my own computer, it takes me 5682 ms to run! Yes there is difference on hardware of course, but it runs about 5 times faster on Codeforces! I am wondering if there is any optimization on Codeforces servers or compile instructions which makes it run as fast as this?

UPD: That is actually because of -O2 compile flag. Never knew it affects the running time as much as making it run 5 times faster.

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5 years ago, # |
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I guess the reason is compiler flag to optimize code.

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Maybe I am wrong. But let us find out the answer.

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    5 years ago, # ^ |
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    Yes, Yes. You are right. Actually this is because of -O2 flag. I didn't know this flag is effective like this! I should have probably tested running the code with Codeforces compile flags before posting the blog.

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5 years ago, # |
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