program ltest2

      implicit none

      integer(4), parameter :: novol  =  4759135      ! number of volumes
      integer(4), parameter :: noq    = 18647560      ! total number of flows
      real   (4), parameter :: dt     =    900.0      ! time step size

      real   (4) volume0(novol)                       ! volume start of time step
      real   (4) volume1(novol)                       ! volume end of time step
      real   (4) flow ( noq)                          ! number of flows
      integer(4) ipnt(4,noq)                          ! exchange pointer
      real   (4) dif                                  ! time step size
      integer    itim1, itim2                         ! times in the files
      integer    ierr                                 ! eof indicator
      integer    iq, ivol                             ! loop variables
      integer    ifrom, ito                           ! from and to volume numbers
      integer    i, j                                 ! loop variables

      open  ( 20, file='report.out' )
      open  ( 21, file='stacks_355-355.vol', form='binary' )
      open  ( 22, file='stacks_355-355.flo', form='binary' )
      open  ( 23, file='stacks_355-355.poi', form='binary' )
      open  ( 31, file='volume_3.out', recl=200 )
      read  ( 23 ) ipnt

      read  ( 21, iostat=ierr ) itim1, volume1
      write ( 31, * ) itim1, volume1(3)
      read  ( 22 ) itim2, flow
      write ( 20, * ) 'Time = ',itim1
      do j = 1, 3
         do iq = 1, noq
            if ( ipnt(1,iq) .gt. 0 ) volume1(ipnt(1,iq)) = volume1(ipnt(1,iq)) - flow(iq)*dt
            if ( ipnt(2,iq) .gt. 0 ) volume1(ipnt(2,iq)) = volume1(ipnt(2,iq)) + flow(iq)*dt
            if ( ipnt(1,iq) .eq. 3 .or. ipnt(2,iq) .eq. 3 ) then
               write ( 31, '(3i8,3e16.7)' ) iq, ipnt(1,iq), ipnt(2,iq) , flow(iq), flow(iq)*dt, volume1(3)
            endif
         enddo
         read  ( 21, iostat=ierr ) itim1, volume0
         write ( 31, * ) itim1, volume0(3)
         do ivol = 1, novol
            if ( abs(volume0(ivol)-volume1(ivol)) .gt. 1.0E-4*volume1(ivol) )            &
     &     write ( 20, '(i8,3e15.6)' ) ivol, volume0(ivol), volume1(ivol), abs(volume0(ivol)-volume1(ivol))/volume1(ivol)
         enddo
         write ( 31, '(i8,3e15.6)' ) 3, volume0(3), volume1(3), abs(volume0(3)-volume1(3))/volume1(3)
         write ( 20, * ) 'Time = ',itim1
         read  ( 22 ) itim2, flow
         volume1 = volume0
      enddo

      stop
      end