#include <stdio.h>
#include "mpi.h"

main (argc, argv)
int argc;
char *argv[];
{
   int rank, n, i, message;
   MPI_Status status;

   MPI_Init (&argc, &argv);

   MPI_Comm_size (MPI_COMM_WORLD, &n);

   MPI_Comm_rank (MPI_COMM_WORLD, &rank);

   if (rank==0) {  /* Process 0 will output data */
      printf ("\n Hello from process %3d", rank);
      for (i=1;i<n;i++) {
         MPI_Recv (&message, 1, MPI_INT, MPI_ANY_SOURCE, MPI_ANY_TAG,
                   MPI_COMM_WORLD, &status);
         printf ("\n Hello from process %3d", message);
      }
   }
   else MPI_Send (&rank, 1, MPI_INT, 0, 111, MPI_COMM_WORLD);

   MPI_Finalize ();
}