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