20
15 13 12 14 11 16 20 19 18 17 
11 20 12 15 19 18 13 14 16 17 
13 19 15 11 14 20 18 16 17 12 
19 15 11 20 13 18 14 12 16 17 
13 12 20 11 18 16 17 14 15 19 
15 17 20 11 19 18 12 13 14 16 
17 16 12 14 20 19 11 13 15 18 
14 15 19 17 12 18 20 16 13 11 
16 18 20 17 14 12 19 11 15 13 
19 14 20 12 13 17 11 18 16 15 
3 9 6 7 5 8 4 2 1 10 
2 3 9 7 10 4 1 5 6 8 
6 1 4 9 8 5 10 7 3 2 
3 1 7 6 2 4 10 9 5 8 
5 10 7 2 1 4 6 3 9 8 
3 8 5 10 6 7 9 1 4 2 
4 1 10 3 8 9 5 2 7 6 
10 5 6 8 7 1 9 3 2 4 
5 3 6 9 10 8 4 2 7 1 
2 7 8 9 10 6 3 4 1 5 
forbidden 1 18
forbidden 1 20
forbidden 2 12
forbidden 2 15
forbidden 2 16
forbidden 2 17
forbidden 2 19
forbidden 2 20
forbidden 3 11
forbidden 3 12
forbidden 3 13
forbidden 3 14
forbidden 3 15
forbidden 3 16
forbidden 3 17
forbidden 4 12
forbidden 4 14
forbidden 4 15
forbidden 4 17
forbidden 4 20
forbidden 5 11
forbidden 5 14
forbidden 5 15
forbidden 5 16
forbidden 5 17
forbidden 6 13
forbidden 6 14
forbidden 6 17
forbidden 6 18
forbidden 7 14
forbidden 7 16
forbidden 7 19
forbidden 8 11
forbidden 8 12
forbidden 8 13
forbidden 8 15
forbidden 8 16
forbidden 8 18
forbidden 8 19
forbidden 9 13
forbidden 9 14
forbidden 9 15
forbidden 9 16
forbidden 10 11
forbidden 10 12
forbidden 10 13
forbidden 10 15
forbidden 10 16
forbidden 10 18
forbidden 10 19
forbidden 10 20