program hello
      include 'mpif.h'
      integer rank, size, ierr
      
      call MPI_INIT(ierr)
      call MPI_COMM_RANK(MPI_COMM_WORLD,rank,ierr)
      call MPI_COMM_SIZE(MPI_COMM_WORLD,size,ierr)
      
      print *,"Hello world! I am ",rank," of ",size
      
      call MPI_FINALIZE(ierr)
      stop
      end