4 5

1   1    1    1    0

1   0   -1    0    0

1  -1    0    0    2

1   1    1   -1    0

4 5

1  -1    1    0    2

1   1   -2   -2   -1

1  -1    0    2    3

1   1    0    0   -1

10 5

1   1    0    1    0

1   1    1    0    0

1   0    1    1    2

1  -3    1   -1    8

1  -3    1    1    8

1   0    1   -1    2

1   1    0   -1    0

1   1   -2   -1    0

1  -1   -3    2    6

1   1   -5   -2    2