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