RedPanda-CPP/Templates/OpenMP_cpp.txt

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#include <omp.h>
#include <stdio.h>
// not using iostream here due to output ordering issues
// iostream tends to output each part between <<'s separately to the console,
// which can lead to random output if multiple threads are doing the same
// thing.
// printf will generally output the whole result string in one go, so results
// of separate printf calls, even from different threads, will remain intact
// Another fix, other than using printf, would be to give each thread its own
// place to store output temporarily (a stringstream), and then output the whole
// result in one go.
int main() {
#pragma omp parallel num_threads(2)
printf("Hi, I'm thread number %d!\n",omp_get_thread_num());
#pragma omp parallel for num_threads(2)
for(int i = 0;i < 20;i++) {
printf("\nThread number %d, executing iteration %d...",omp_get_thread_num(),i);
}
}