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