Seferovic's blog

Lambda Functions lead to TLE!
By Seferovic, history, 9 months ago, In English

The only difference between the two submissions is using a lambda function vs a global function. Lambda functions made the runtime around 7 times slower.

What do you think this is because?

AC: 255501228

TLE: 255500672

so should we always prefer global functions over lambdas then?

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9 months ago, # |
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Auto comment: topic has been updated by Mr.Whitebird (previous revision, new revision, compare).

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9 months ago, # |
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My theory is that its because lambda functions are created each time solve() is called: in the worst case they get created 1000 times each and maybe that's the cause of slowdown

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    9 months ago, # ^ |
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    Tysm, as ZergTricky has shown, the reason was pragmas. This is good motivation to learn how they actually work!

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9 months ago, # |
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Why you use endl though? '\n' doesn't flush the output when combining with cin.tie(0) so it runs faster.

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    9 months ago, # ^ |
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    well I figured 1000 cases wont matter much so I usually use endl for debug purposes if the output stream wont be too crowded

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9 months ago, # |
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Just removed pragmas from your code. Don't use them if you don't understand when. https://codeforces.net/contest/1862/submission/255506582

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    9 months ago, # ^ |
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    woah! Thank you so much! I should really learn how pragmas work...

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