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