// MPI1.cpp : 定义控制台应用程序的入口点。

//

#include "stdafx.h"

#include "mpi.h"

#include <Windows.h>

#include <stdio.h>

#include <math.h>

int main(int argc, char* argv[])

{

	int done=0,n,myid,numproces,i;

	double mypi,pi,sum;

	double startwtime,endwtime;

	int namelen;

	char processor_name[MPI_MAX_PROCESSOR_NAME];

	MPI_Init(&argc,&argv);

	MPI_Comm_rank(MPI_COMM_WORLD,&myid);

	MPI_Comm_size(MPI_COMM_WORLD,&numproces);

	MPI_Get_processor_name(processor_name,&namelen);

	fprintf(stderr,"Process %d on %s\n",myid,processor_name);

	fflush(stderr);

	n=0;

	while(!done)

	{

		if(myid==0)

		{

			printf("输入一个数字不超过：(0退出)");

			fflush(stdout);

			scanf_s("%d",&n);

			startwtime=MPI_Wtime();

		}

		MPI_Bcast(&n,1,MPI_INT,0,MPI_COMM_WORLD);

		if(n==0)

			done=1;

		else

		{

			sum=0.0;

			for(i=myid+1;i<=n;i+=numproces)

				sum+=i;

			mypi=sum;

			MPI_Reduce(&mypi,&pi,1,MPI_DOUBLE,MPI_SUM,0,MPI_COMM_WORLD);

			if(myid==0)

			{

				printf("结果%.16f\n",pi);

				endwtime=MPI_Wtime();

				printf("时间=%f\n",endwtime-startwtime);

			}

		}

	}

	MPI_Finalize;

	printf("时间");

	system("pause");

	return 0;

}

运行结果如下：