2 4

  1  1  0 -1

  1 -1  1  0

-1

8 7

  1  0  1  0 -1  0  0

  1  0 -1  0  1  0  0

  1  1  0  0  0 -1  0

  1 -1  0  0  0  1  0

  1  0  1  0  0  0 -1

  1  0 -1  0  0  1  0

  1  0 -1  1  0  0 -1

  1  0  0 -1  0  1  0