program main
  implicit none
  integer*8::DA,DB
  integer*8,allocatable::a(:)
  integer::i
  read *,DA
  allocate(a(0:DA))
  read *,a

  do i=DA, 3, -1
     a(i-2) = a(i-2) + a(i)
  end do

  do i=2, 0, -1
     if(a(i).ne.0) exit
  end do
  print '(i0)',MAX(i,0)
  call aprinter(a(0:MAX(i,0)))
contains
  subroutine aprinter(array)
    integer*8::array(:)
    character*32::cformat='(i0,     (1x,i0))'
    write(cformat(5:9),'(i0)'),size(array)
    write(*,cformat) array
  end subroutine aprinter
end program main