subroutine WRITECONFIG(S, L)
  implicit none
  integer*4, intent(in) :: L
  integer*2, intent(out) :: S(1:L,1:L)
  integer*4 :: SEED, i, j
  real*8 :: genrand_real2

  SEED = 23456
  call init_genrand(SEED)

  do i = 1, L
    do j = 1, L
      S(i, j) = merge(1, -1, genrand_real2() < .5d0)
    enddo
  enddo

  open(1, file = "configuration.conf")

  do i = 1, L
    do j = 1, L
      if (S(i, j) == 1) then
        write(1, *) i, j
      endif
    enddo
  enddo

  close(1)
end subroutine WRITECONFIG