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/******************************************************************************
* FILE: omp_orphan.c
* DESCRIPTION:
* OpenMP Example - Parallel region with an orphaned directive - C/C++ Version
* This example demonstrates a dot product being performed by an orphaned
* loop reduction construct. Scoping of the reduction variable is critical.
* AUTHOR: Blaise Barney 5/99
* LAST REVISED: 04/06/05
******************************************************************************/
#include <omp.h>
#include <stdio.h>
#include <stdlib.h>
#define VECLEN 100
float a[VECLEN], b[VECLEN], sum;
float dotprod ()
{
int i,tid;
tid = omp_get_thread_num();
#pragma omp for reduction(+:sum)
for (i=0; i < VECLEN; i++)
{
sum = sum + (a[i]*b[i]);
printf(" tid= %d i=%d\n",tid,i);
}
return(sum);
}
int main (int argc, char *argv[])
{
int i;
for (i=0; i < VECLEN; i++)
a[i] = b[i] = 1.0 * i;
sum = 0.0;
#pragma omp parallel
sum = dotprod();
printf("Sum = %f\n",sum);
return 0;
}
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