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