0 -> 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19
1 -> 1, 2, 7, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19
2 -> 2, 7, 11, 12, 15, 16, 17, 18
3 -> 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19
4 -> 4, 12, 15, 17
5 -> 5, 9, 10, 11, 12, 13, 14, 15, 17, 19
6 -> 2, 6, 7, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19
7 -> 7, 15, 16, 17, 18
8 -> 8
9 -> 9
10 -> 10, 15, 19
11 -> 11, 12, 15, 17
12 -> 12, 15, 17
13 -> 13, 14, 15, 19
14 -> 14, 15
15 -> 15
16 -> 15, 16
17 -> 17
18 -> 15, 18
19 -> 19