7
0 16 18 14 13 12 13 
16 0 10 8 7 8 7 
18 10 0 8 9 8 7 
14 8 8 0 5 4 3 
13 7 9 5 0 5 2 
12 8 8 4 5 0 3 
13 7 7 3 2 3 0