Given an undirected graph, finding either a minimum 2-edge-connected spanning subgraph or a minimum 2vertex-connected (biconnected) spanning subgraph is MaxSNP-hard. We show that ...
Artur Czumaj, Michelangelo Grigni, Papa Sissokho, ...
Abstract. We present new approximation schemes for various classical problems of finding the minimum-weight spanning subgraph in edge-weighted undirected planar graphs that are re...
We give the first polynomial-time approximation scheme (PTAS) for the Steiner forest problem on planar graphs and, more generally, on graphs of bounded genus. As a first step, w...
In this paper we introduce and study cooperative variants of the Traveling Salesperson Problem. In these problems a salesperson has to make deliveries to customers who are willing ...
— We show that for every fixed k, there is a linear time algorithm that decides whether or not a given graph has a vertex set X of order at most k such that G − X is planar (w...