yassin_'s blog

Undefined Behaviour of wtf?
By yassin_, history, 7 years ago, In English

This is about 845B - Luba And The Ticket from educational round 27.

My code got AC for C++14 34715622 and TLE for C++11 34715609. Can anyone tell me why? Diagnostics also TLEs, so I couldn't use that to check for undefined behaviour.

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7 years ago, # |
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I think culprit is slow to_string().

I resubmitted your code as 34719330 with string x(to_string(i)) call replaced by

char buff[20];
sprintf(buff, "%d", i);
string x(buff);

under C++11 5.1.0, and it works in ~170 ms.

Presumably implementation of to_string() was slow in version 5.1.0 of compiler and improved at some version <= 6.4.

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7 years ago, # |
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this is irrelevant but which version of CLion are you using for Jhelper. Did you buy one?

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    7 years ago, # ^ |
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    2017.2 you can get it for free with a university email address

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