6

 0 10 20 40 10 30
10  0 20 30  5 25
30 20  0 10 25  5
40 30 10  0 30 10
10  5 25 10  0 20
30 25  5 30 20  0

 0  2  5  1 10  5
 2  0  6 10  1 10
 5  6  0 20  1 30
 1 10 20  0 40  1
10  1  1 40  0 50
 5 10 30  1 50  0
