1

1

1

1

1

1

1

1

1

2

1

1

1

1

1

1

1

1

1

1

1

1.

1

1

1

1

1

1

1+2

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1-2

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1