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