The Connected P -Median Problem on Cactus Graphs

This study deals with the facility location problem of locating a set V p of p facilities on a graph such that the subgraph induced by V p is connected. We consider the connected p -median problem on a cactus graph G whose vertices and edges have nonnegative weights. The aim of a connected p -median problem is to minimize the sum of weighted distances from every vertex of a graph to the nearest vertex in V p . We provide an O n 2 p 2 time algorithm for the connected p -median problem, where n is the number of vertices.