>>writegraph3d planar <<
1 0 0 0 2 3 6 4
2 0 0 0 1 5 3
3 0 0 0 1 2 7 6
4 0 0 0 1 7 5
5 0 0 0 2 4 7
6 0 0 0 3 7 1
7 0 0 0 4 6 3 5
0
