/****************************************************************************** * FILE: omp_reduction.c * DESCRIPTION: * OpenMP Example - Combined Parallel Loop Reduction - C/C++ Version * This example demonstrates a sum reduction within a combined parallel loop * construct. Notice that default data element scoping is assumed - there * are no clauses specifying shared or private variables. OpenMP will * automatically make loop index variables private within team threads, and * global variables shared. * AUTHOR: Blaise Barney 5/99 * LAST REVISED: 04/06/05 ******************************************************************************/ #include #include #include int main (int argc, char *argv[]) { int i, n; float a[100], b[100], sum; /* Some initializations */ n = 100; for (i=0; i < n; i++) a[i] = b[i] = i * 1.0; sum = 0.0; #pragma omp parallel for reduction(+:sum) for (i=0; i < n; i++) sum = sum + (a[i] * b[i]); printf(" Sum = %f\n",sum); return 0; }