Question 28
Given $n$ points can one build $n-1$ roads, so that each road joins two points, the shortest distance between any two points along the roads belongs to $\{1, 2, 3, \ldots, n(n-1)/2\}$, and given any element of $\{1, 2, 3, \ldots, n(n-1)/2\}$ one can find two points such that the shortest distance between them along the roads is that element?