Fast Algorithms for Diameter-Optimally Augmenting Paths and Trees
Abstract
We consider the problem of augmenting an n-vertex graph embedded in a metric space, by inserting one additional edge in order to minimize the diameter of the resulting graph. We present exact algorithms for the cases when (i) the input graph is a path, running in O(nlog3n) time, and (ii) the input graph is a tree, running in O(n2logn) time. We also present an algorithm for paths that computes a (1+𝜀)-approximation in O(n+1/𝜀3) time.
Communicated by Marek Chrobak