N=30
0: 1 5 9 -1
1: 0 2 -1
2: 1 3 -1
3: 2 4 -1
4: 3 5 -1
5: 4 0 -1
6: 7 8 9 -1
7: 6 8 -1
8: 7 6 -1
9: 0 6 -1
10: 11 15 19 -1
11: 10 12 -1
12: 11 13 -1
13: 12 14 -1
14: 13 15 -1
15: 14 10 -1
16: 17 18 19 -1
17: 16 18 -1
18: 17 16 -1
19: 10 16 -1
20: 21 25 29 -1
21: 20 22 -1
22: 21 23 -1
23: 22 24 -1
24: 23 25 -1
25: 24 20 -1
26: 27 28 29 -1
27: 26 28 -1
28: 27 26 -1
29: 20 26 -1
