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/******************************************************************************
* FILE: omp_workshare2.c
* DESCRIPTION:
* OpenMP Example - Sections Work-sharing - C/C++ Version
* In this example, the OpenMP SECTION directive is used to assign
* different array operations to threads that execute a SECTION. Each
* thread receives its own copy of the result array to work with.
* AUTHOR: Blaise Barney 5/99
* LAST REVISED: 04/06/05
******************************************************************************/
#include <omp.h>
#include <stdio.h>
#include <stdlib.h>
#define N 50
int main (int argc, char *argv[]) {
int i, nthreads, tid;
float a[N], b[N], c[N];
/* Some initializations */
for (i=0; i<N; i++)
a[i] = b[i] = i * 1.0;
#pragma omp parallel shared(a,b,nthreads) private(c,i,tid)
{
tid = omp_get_thread_num();
if (tid == 0)
{
nthreads = omp_get_num_threads();
printf("Number of threads = %d\n", nthreads);
}
printf("Thread %d starting...\n",tid);
#pragma omp sections nowait
{
#pragma omp section
{
printf("Thread %d doing section 1\n",tid);
for (i=0; i<N; i++)
{
c[i] = a[i] + b[i];
printf("Thread %d: c[%d]= %f\n",tid,i,c[i]);
}
}
#pragma omp section
{
printf("Thread %d doing section 2\n",tid);
for (i=0; i<N; i++)
{
c[i] = a[i] * b[i];
printf("Thread %d: c[%d]= %f\n",tid,i,c[i]);
}
}
} /* end of sections */
printf("Thread %d done.\n",tid);
} /* end of parallel section */
return 0;
}
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