The network is the same as on p433, except that
the mileages have changed.

Here are the correct lengths for the edges, in
lexicographic order.

ARC     COST
1-2       9
1-5       8
1-6      10
2-3      10
2-4       7
3-4       9
3-9      11
4-5       4
4-7       2
4-8       1
4-9       4
5-6       6
5-7       2
5-11      7
6-7       4
6-11      5
6-12     15
7-8       1
7-10      4
7-11      5
7-14     22
8-9       3
8-10      2
8-13      9
9-10      6
9-13      8
10-12    18
10-13     7
10-14    10
11-14    14
11-15    10
12-15     9
13-14     8
14-15    12