1 /******************************************************************************
2 * FILE: omp_workshare1.c
3 * DESCRIPTION:
4 *   OpenMP Example - Loop Work-sharing - C/C++ Version
5 *   In this example, the iterations of a loop are scheduled dynamically
6 *   across the team of threads.  A thread will perform CHUNK iterations
7 *   at a time before being scheduled for the next CHUNK of work.
8 * AUTHOR: Blaise Barney  5/99
9 * LAST REVISED: 04/06/05
10 ******************************************************************************/
11 #include <omp.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #define CHUNKSIZE   10
15 #define N       100
16 
17 int main (int argc, char *argv[]) {
18 
19 int nthreads, tid, i, chunk;
20 float a[N], b[N], c[N];
21 
22 /* Some initializations */
23 for (i=0; i < N; i++)
24   a[i] = b[i] = i * 1.0;
25 chunk = CHUNKSIZE;
26 
27 #pragma omp parallel shared(a,b,c,nthreads,chunk) private(i,tid)
28   {
29   tid = omp_get_thread_num();
30   if (tid == 0)
31     {
32     nthreads = omp_get_num_threads();
33     printf("Number of threads = %d\n", nthreads);
34     }
35   printf("Thread %d starting...\n",tid);
36 
37   #pragma omp for schedule(dynamic,chunk)
38   for (i=0; i<N; i++)
39     {
40     c[i] = a[i] + b[i];
41     printf("Thread %d: c[%d]= %f\n",tid,i,c[i]);
42     }
43 
44   }  /* end of parallel section */
45 
46   return 0;
47 }
48