Approximation algorithms for clique-transversal sets and clique-independent sets in cubic graphs

  • Authors:
  • Zuosong Liang;Erfang Shan

  • Affiliations:
  • Department of Mathematics, Shanghai University, Shanghai 200444, China;Department of Mathematics, Shanghai University, Shanghai 200444, China

  • Venue:
  • Information Processing Letters
  • Year:
  • 2011

Quantified Score

Hi-index 0.89

Visualization

Abstract

A clique-transversal set S of a graph G is a subset of vertices intersecting all the cliques of G, where a clique is a complete subgraph maximal under inclusion and having at least two vertices. A clique-independent set of the graph G is a set of pairwise disjoint cliques of G. The clique-transversal number@t"C(G) of G is the cardinality of the smallest clique-transversal set in G and the clique-independence number@a"C(G) of G is the cardinality of the largest clique-independent set in G. This paper proves that determining @t"C(G) and @a"C(G) is NP-complete for a cubic planar graph G of girth 3. Further we propose two approximation algorithms for determining @t"C(G) and @a"C(G) in a cubic graph G.