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