arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1503.00091cs.DM
收藏

无$P_6$图的某些子类在多项式时间内的有效控制

Efficient Domination for Some Subclasses of $P_6$-Free Graphs in Polynomial Time

Andreas Brandstädt, Elaine M. Eschen, Erik Friese

摘要:

设$G$是一个有限无向图。一个顶点{ \em支配}它自己和它在$G$中的所有邻居。如果$G$的每个顶点都被$D$的一个顶点支配,则顶点集$D$是$G$的{ \em有效支配集}(\emph{e.d.} \). \emph{Efficient Domination}(ED)问题,它要求存在一个ED。在$G$中,即使对于非常有限的图类,例如无$P_7$弦图,也已知是\NP完全的。图$G$上的ED问题可以归结为图$G$平方上的最大权独立集(MWIS)问题. ED问题的复杂性对于$P_6$ -free图是一个开放的问题,甚至对于$P_6$ -free弦图的子类也是开放的。在本文中,我们证明了$P_6$ -自由弦图的平方,有一个e. d。是弦的;这甚至适用于更大类的($P_6$,house,hole,domino)-free图。这意味着ED/WeightedED对于($P_6$,house,hole,domino)-free图,特别是对于$P_6$ -free弦图,在多项式时间内是可解的.此外,基于我们的结果,$P_6$ -自由图的平方,有一个e. d.是无洞的,并给出了关于奇反洞的一些性质,证明了具有e. d.都很完美这意味着ED/WeightedED对于($P_6$,house)-free图和($P_6$,bull)-free图都是多项式时间可解的(($P_6$,house,hole,domino)-free图的时间界优于($P_6$,house)-free图的时间界).无$P_6$图的ED问题的复杂性仍然是一个悬而未决的问题。

英文摘要:

Let $G$ be a finite undirected graph. A vertex {\em dominates} itself and all its neighbors in $G$. A vertex set $D$ is an {\em efficient dominating set} (\emph{e.d.}\ for short) of $G$ if every vertex of $G$ is dominated by exactly one vertex of $D$. The \emph{Efficient Domination} (ED) problem, which asks for the existence of an e.d.\ in $G$, is known to be \NP-complete even for very restricted graph classes such as $P_7$-free chordal graphs. The ED problem on a graph $G$ can be reduced to the Maximum Weight Independent Set (MWIS) problem on the square of $G$. The complexity of the ED problem is an open question for $P_6$-free graphs and was open even for the subclass of $P_6$-free chordal graphs. In this paper, we show that squares of $P_6$-free chordal graphs that have an e.d. are chordal; this even holds for the larger class of ($P_6$, house, hole, domino)-free graphs. This implies that ED/WeightedED is solvable in polynomial time for ($P_6$, house, hole, domino)-free graphs; in particular, for $P_6$-free chordal graphs. Moreover, based on our result that squares of $P_6$-free graphs that have an e.d. are hole-free and some properties concerning odd antiholes, we show that squares of ($P_6$, house)-free graphs (($P_6$, bull)-free graphs, respectively) that have an e.d. are perfect. This implies that ED/WeightedED is solvable in polynomial time for ($P_6$, house)-free graphs and for ($P_6$, bull)-free graphs (the time bound for ($P_6$, house, hole, domino)-free graphs is better than that for ($P_6$, house)-free graphs). The complexity of the ED problem for $P_6$-free graphs remains an open question.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑