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