Ty For this problem, let T (V, E) be a graph that is undirected (so that if u is in Adyje), then v is in Adju), and is acyclic. Simply put, T forms a tree. However, T is unrooted, which means that there is no notion of a root or starting vertex that T does have leaves: these are the vertices with just one neighbor. [For completeness, we note that if T is a singleton verte with no neighbors, it is also a leaf But note An unrooted tree also has something called a center. v) be the number of edges on the the longest (simple) path in T that starts at v. Note that the vertex at 'the other end" of such a path must be a leaf, since path could otherwise be extended to reach a vertex that is even farther away from v. A vertex w in T is a center of T if it has as small an Mdist as possible: that is, w is a center of T if Mdist(w)mine in (Mdist(o). So w is as close to being in the center of a longest path in T as possible