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Same code got TLE in C++11 but AC in C++17
By anupam, history, 5 years ago, In English

Same code got TLE in GNU C++11 and got AC in GNU C++17. Can someone please tell me the reason behind it?

TLE (C++11): http://codeforces.me/contest/1520/submission/115347126

AC (C++17): http://codeforces.me/contest/1520/submission/115347176

Thanks!

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5 years ago, hide # |
 
Vote: I like it +7 Vote: I do not like it

Running the same code in custom invocation and printing v.size() gives 81 in C++17 and 9090927 in C++11, so you're iterating over significantly more values when submitting under C++11 per test case. As for why, there appears to be a difference in the implementation of pow, as k takes on the values 1, 11, 111 in C++17 and 1, 11, 110 in C++11. Not sure why that happens though, I think the actual implementation of pow is architecture dependent. In my opinion, it's easier to just not involve floating point computation if possible.

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