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@kaityo256
Created February 5, 2020 14:36
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Intel Compiler vs. GCC
#include <iostream>
#include <random>
struct myrand {
uint32_t operator()() {
return 0;
}
uint32_t max(){
return std::mt19937::max();
}
uint32_t min(){
return 0;
}
};
double run(void) {
myrand mt;
double r = 0.0;
std::uniform_real_distribution<> ud(-1.0, 1.0);
for (int j = 0; j <10000; j++) {
for (int i = 0; i < 10000; i++) {
if (i%2) r += ud(mt);
}
}
return r;
}
int main(){
std::cout << run() << std::endl;
}
@kaityo256
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Yep, you are right, @uTnOJkji5quPSNE5.

I should say, "the Mersenne Twister implementation included in GCC was fast". Anyway, I'm not sure why.

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