Approximation Algorithms for Digraph Width Parameters

Fuente: arXiv

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Bibliographische Detailangaben
Hauptverfasser:	Kintali, Shiva, Kothari, Nishad, Kumar, Akash
Format:	Preprint
Veröffentlicht:	2011
Schlagworte:	Data Structures and Algorithms
Online-Zugang:	Acceder al recurso
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_version_	1866918514882772992
author	Kintali, Shiva Kothari, Nishad Kumar, Akash
author_facet	Kintali, Shiva Kothari, Nishad Kumar, Akash
contents	Several problems that are NP-hard on general graphs are efficiently solvable on graphs with bounded treewidth. Efforts have been made to generalize treewidth and the related notion of pathwidth to digraphs. Directed treewidth, DAG-width and Kelly-width are some such notions which generalize treewidth, whereas directed pathwidth generalizes pathwidth. Each of these digraph width measures have an associated decomposition structure. In this paper, we present approximation algorithms for all these digraph width parameters. In particular, we give an O(sqrt{logn})-approximation algorithm for directed treewidth, and an O({\log}^{3/2}{n})-approximation algorithm for directed pathwidth, DAG-width and Kelly-width. Our algorithms construct the corresponding decompositions whose widths are within the above mentioned approximation factors.
format	Preprint
id	arxiv_https___arxiv_org_abs_1107_4824
institution	arXiv
publishDate	2011
record_format	arxiv
spellingShingle	Approximation Algorithms for Digraph Width Parameters Kintali, Shiva Kothari, Nishad Kumar, Akash Data Structures and Algorithms Several problems that are NP-hard on general graphs are efficiently solvable on graphs with bounded treewidth. Efforts have been made to generalize treewidth and the related notion of pathwidth to digraphs. Directed treewidth, DAG-width and Kelly-width are some such notions which generalize treewidth, whereas directed pathwidth generalizes pathwidth. Each of these digraph width measures have an associated decomposition structure. In this paper, we present approximation algorithms for all these digraph width parameters. In particular, we give an O(sqrt{logn})-approximation algorithm for directed treewidth, and an O({\log}^{3/2}{n})-approximation algorithm for directed pathwidth, DAG-width and Kelly-width. Our algorithms construct the corresponding decompositions whose widths are within the above mentioned approximation factors.
title	Approximation Algorithms for Digraph Width Parameters
topic	Data Structures and Algorithms
url	https://arxiv.org/abs/1107.4824

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