/* A simple example of MPI broadcast. */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <mpi.h>

int main (int argc, char *argv[])
{
  int rank, size, aNumber, i, maxIter;
  const int root=0;
  char hostname[256];

  MPI_Init (&argc, &argv);	/* starts MPI */
  MPI_Comm_rank (MPI_COMM_WORLD, &rank);	/* get current process id */
  MPI_Comm_size (MPI_COMM_WORLD, &size);	/* get number of processes */
  gethostname(hostname, 255);	/* get host name */

  maxIter = 6;

  if(rank == 0) {
    aNumber = 17;
  }
  else {
    aNumber = -1;
  }

  printf("[Rank %d on host %s]: Before Bcast, aNumber is %d\n", rank, hostname, aNumber);

  for (i=0; i<maxIter; i++) {
    MPI_Bcast(&aNumber, 1, MPI_INT, root, MPI_COMM_WORLD);
  }

  printf("[Rank %d on host %s]: After Bcast, aNumber is %d\n", rank, hostname, aNumber);

  MPI_Finalize();
  return 0;
}