用OpenMP编写并行程序实现求1+…100000

[杰]

#include <omp.h>
#include <stdio.h>
#include <stdlib.h>
#define   N      100000
int main (int argc, char *argv[]) 
{
double sum=0;
int i;
/* Some initializations */
for (i=0; i < N; i++)
  #pragma omp parallel for reduction(+:sum) private(i) shared(sum)
for (i=0; i<N; i++)
    {
    sum = sum+i;
    }
printf("sum=%d\n",sum);
return 0;
}

编译时出现错误：‘sum’ appears more than once in data clauses

[晓枫gis]

omp中，[clause]不允许变量被两个同类的clause约束，前面已经有了reduction[operator:list]规约了sum变量，所以后面shared[list]就不能再对sum进行约束。

[MoreWindows]

OpenMP没搞过，不过我写了一篇MPI的《Windows系统下搭建MPI环境》 http://blog.csdn.net/morewindows/article/details/6823436