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