Hello Codeforces.
I made two identical submissions on the same problem.
C++ 17(64bit) — 842ms.
C++ 20(64bit) — 1138ms.
Does anyone know why the time differs so much?
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Hello Codeforces.
I made two identical submissions on the same problem.
C++ 17(64bit) — 842ms.
C++ 20(64bit) — 1138ms.
Does anyone know why the time differs so much?
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In my opinion C++20 is usually much quicker. Maybe it depends on the code.
Removing two lines containing the following makes both c++ versions run in the same amount of time:
C++17: 623ms/623ms
C++20: 623ms/624ms
Obviously, the problem was that compilers couldn't fully optimize away the unused call, but I don't know any details why such a difference.