program ch1213
implicit none
integer , parameter :: n=1000000
integer , dimension(1:n) :: x
real    , dimension(1:n) :: y
integer :: i
real :: t,t1,t2,t3,t4,t5
character*10 :: comment
  open(unit=10,file='ch1213.txt',form='unformatted')
  call cpu_time(t)
  t1=t
  comment=' Intial '
  print 100,comment,t1
  do i=1,n
    x(i)=i
  end do
  call cpu_time(t)
  t2=t-t1
  comment = ' Integer '
  print 100,comment,t2
  y=real(x)
  call cpu_time(t)
  t3=t-t1-t2
  comment = ' real '
  print 100,comment,t2
  write(10) x
  call cpu_time(t)
  t4=t-t1-t2-t3
  comment = ' i write '
  print 100,comment,t4
  write(10) y
  call cpu_time(t)
  t5=t-t1-t2-t3-t4
  comment = ' r write '
  print 100,comment,t5
  100 format(1x,a,2x,f7.3)
end program ch1213