program hello
      include 'mpif.h'
      integer rank, size, ierror, tag, status(MPI_STATUS_SIZE)
      character(12) message
      
      call MPI_INIT(ierror)
      call MPI_COMM_SIZE(MPI_COMM_WORLD, size, ierror)
      call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierror)
      tag=100
      if (rank.eq.0)then
              message='Hello, world'
              do i=1, size-1
                call MPI_SEND(message,12,MPI_CHARACTER,i,
     &             tag,MPI_COMM_WORLD,ierror)
              enddo
      else
              call MPI_RECV(message,12,MPI_CHARACTER,0,
     &             tag,MPI_COMM_WORLD,status,ierror)

      endif
      open(unit=1,file='test.out',status='unknown')
      write(1,*) 'processor', rank, ':', message
      close(1)
      print*, 'processor', rank, ':', message
      call MPI_FINALIZE(ierror)
      end