num_runs Subroutine

  subroutine num_runs (n)
    implicit none
    integer, intent (out) :: n

    do 
100    continue
       call text
       call text ('How many runs should be done? (n > 1)')
       read (interactive_input, *, err=100) n
       if (n < 2) then
          call try_again
       else
          return
       end if
    end do
  end subroutine num_runs