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