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