#include <stdio.h>
#include <mpi.h>
#define comm MPI_COMM_WORLD

int main(int arge, char **argv)
{
MPI_Status status;
MPI_Init(&arge,&argv);
int N = 12;
int ai, rank, size, del, i0, imax, i, s=0, s1=0;

MPI_Request request;

MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);

int a[N];

del = N/size;
i0 = rank*del;
ai = i+1;
imax = i0 + del;
if (rank = size - 1)
{
imax = N;
}
for (i=i0;i<imax;i++)
{
a[i] =i+1;
s1+=a[i];
}

MPI_Reduce(&s1, &s, 1, MPI_INT, MPI_SUM, 0, comm);
printf("rank=%d\n, size=%d\n, i0=%d\n, imax=%d\n, s1=%d\n, s=%d\n, a[i0]=%d\n", rank, size,i0,imax,s1,s,a[i0]);
printf("Сумма составила: %i", s);


MPI_Finalize();
return 0;
}