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