what's the print?
#include <stdio.h>
#include <mpi.h>
int main(int argc , char **argv)
{
int size, rank;
MPI_Init data;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &size);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
data = rank;
MPI_Bcast(&data, 1, MPI_INT, 3, MPI_COMM_WORLD);
printf("rank %d: data=%lf\n", rank, data);
MPI_Finalize();
return 0;