Information Processing Letters ( IF 0.5 ) Pub Date : 2021-02-04 , DOI: 10.1016/j.ipl.2021.106105 Ambroise Baril , Riccardo Dondi , Mohammad Mehdi Hosseinzadeh
Finding cohesive subgraphs is a fundamental problem for the analysis of graphs. Clique is a classical model of cohesive subgraph, but several alternative definitions have been given in the literature. In this paper we consider the γ-complete graph model, which is based on relaxing the degree constraint of the clique model, that is is a γ-complete graph, with , if and only if every vertex of S has degree at least in . In this contribution, we investigate the complexity of the problem that asks for the γ-complete subgraph of maximum order (that is, maximum number of vertices). We show that the problem is W[1]-hard for when the parameter is order of the subgraph. Moreover, we show that the problem is fixed-parameter tractable when parameterized by the h-index of the input graph, thus solving an open question in the literature.
中文翻译:
γ-完全子图问题的硬度和可延展性
查找内聚子图是图分析的基本问题。派系是内聚子图的经典模型,但文献中已经给出了几种替代定义。在本文中,我们考虑基于完全派系模型的度约束的γ完全图模型,即是一个γ完全图,且仅当S的每个顶点至少具有度 在 。在此贡献中,我们调查了要求最大阶数(即最大顶点数)的γ完全子图的问题的复杂性。我们证明问题在于W [1]-当参数是子图的顺序时。此外,我们表明,当通过输入图的h索引对参数进行参数化时,该问题是固定参数可处理的,从而解决了文献中的一个悬而未决的问题。