20
-2 0
-8 -5
-6 -8
2 4
3 -1
-2 9
-1 -2
8 -1
-5 -9
3 9
5 0
-8 -7
-2 -7
0 -9
7 6
-3 -8
-6 -8
-1 0
3 0
6 6
