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