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