3 0 0 1 0 0 1
2.2761423749
There are six paths to visit the towns: $1$ → $2$ → $3$, $1$ → $3$ → $2$, $2$ → $1$ → $3$, $2$ → $3$ → $1$, $3$ → $1$ → $2$, and $3$ → $2$ → $1$.
The length of the path $1$ → $2$ → $3$ is $\sqrt{\left(0-1\right)^2+\left(0-0\right)^2} + \sqrt{\left(1-0\right)^2+\left(0-1\right)^2} = 1+\sqrt{2}$.
By calculating the lengths of the other paths in this way, we see that the average length of all routes is:
$\frac{\left(1+\sqrt{2}\right)+\left(1+\sqrt{2}\right)+\left(2\right)+\left(1+\sqrt{2}\right)+\left(2\right)+\left(1+\sqrt{2}\right)}{6} = 2.276142...$2 -879 981 -866 890
91.9238815543 There are two paths to visit the towns: $1$ → $2$ and $2$ → $1$. These paths have the same length.
8 -406 10 512 859 494 362 -955 -475 128 553 -986 -885 763 77 449 310
7641.9817824387
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