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