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

int main (int nargs, char** args)
{
  int size0, rank0, size1, rank1, size2, rank2, i;
  MPI_Comm comm1, comm2;

  MPI_Init (&nargs, &args);
  MPI_Comm_size (MPI_COMM_WORLD, &size0);
  MPI_Comm_rank (MPI_COMM_WORLD, &rank0);

  i = rank0%2;
  MPI_Comm_split (MPI_COMM_WORLD, i, rank0, &comm1);
  MPI_Comm_size (comm1, &size1);
  MPI_Comm_rank (comm1, &rank1);

  i = rank0/2;
  MPI_Comm_split (MPI_COMM_WORLD, i, rank0, &comm2);
  MPI_Comm_size (comm2, &size2);
  MPI_Comm_rank (comm2, &rank2);

  printf("size0=%d, rank0=%d, size1=%d, rank1=%d, size2=%d, rank2=%d\n",
         size0, rank0, size1, rank1, size2, rank2);

  MPI_Finalize ();
  return 0;
}