character*(*) function exptim (t)

      character*(*) t

c expand time

      lent = len(t)
      lenx = len(exptim)
      if (lent .eq. 4) then
        exptim = t(:4)
        lenx = min(4, lenx)
      else if (lent .eq. 6) then
        exptim = t(:4)//'/'//t(5:6)
        lenx = min(7, lenx)
      else if (lent .eq. 8) then
        exptim = t(:4)//'/'//t(5:6)//'/'//t(7:8)
        lenx = min(10, lenx)
      else if (lent .eq. 10) then
        exptim = t(:4)//'/'//t(5:6)//'/'//t(7:8)//'@'//t(9:10)
        lenx = min(13, lenx)
      else if (lent .eq. 12) then
        exptim = t(:4)//'/'//t(5:6)//'/'//t(7:8)//'@'//t(9:10)
     2             //':'//t(11:12)
        lenx = min(16, lenx)
      else if (lent .eq. 14) then
        exptim = t(:4)//'/'//t(5:6)//'/'//t(7:8)//'@'//t(9:10)
     2             //':'//t(11:12)//':'//t(13:14)
        lenx = min(19, lenx)
      else
        exptim = t(:4)//'/'//t(5:6)//'/'//t(7:8)//'@'//t(9:10)
     2             //':'//t(11:12)//':'//t(13:14)//'.'//t(15:)
        lenx = min(lent+6, lenx)
      end if
      call exchange(exptim(:lenx), ' ', '0')
      if (lenx .ge. 11) exptim(11:11) = ' '
      return
      end