Title
A New Characterization of $$P_k$$Pk-Free Graphs
Abstract
Let $$G$$G be a connected $$P_k$$Pk-free graph, $$k \ge 4$$k?4. We show that $$G$$G admits a connected dominating set that induces either a $$P_{k-2}$$Pk-2-free graph or a graph isomorphic to $$P_{k-2}$$Pk-2. In fact, every minimum connected dominating set of $$G$$G has this property. This yields a new characterization for $$P_k$$Pk-free graphs: a graph $$G$$G is $$P_k$$Pk-free if and only if each connected induced subgraph of $$G$$G has a connected dominating set that induces either a $$P_{k-2}$$Pk-2-free graph, or a graph isomorphic to $$C_k$$Ck. We present an efficient algorithm that, given a connected graph $$G$$G, computes a connected dominating set $$X$$X of $$G$$G with the following property: for the minimum $$k$$k such that $$G$$G is $$P_k$$Pk-free, the subgraph induced by $$X$$X is $$P_{k-2}$$Pk-2-free or isomorphic to $$P_{k-2}$$Pk-2. As an application our results, we prove that Hypergraph 2-Colorability can be solved in polynomial time for hypergraphs whose vertex-hyperedge incidence graphs is $$P_7$$P7-free.
Year
DOI
Venue
2016
10.1007/s00453-015-9989-6
Algorithmica
Keywords
DocType
Volume
$$P_k$$Pk-free graph, 05C38, 05C69, 05C75, Computational complexity, Connected domination
Journal
75
Issue
ISSN
Citations 
1
0178-4617
1
PageRank 
References 
Authors
0.35
1
2
Name
Order
Citations
PageRank
Eglantine Camby1164.02
Oliver Schaudt29521.74