Change search
ReferencesLink to record
Permanent link

Direct link
The Steiner tree reoptimization problem with sharpened triangle inequality
ETH Zurich.
ETH Zurich.
ETH Zurich.
ETH Zurich.
Show others and affiliations
2011 (English)In: Journal of Discrete Algorithms, ISSN 1570-8667Article in journal (Refereed) Published
Abstract [en]

In this paper, we deal with several reoptimization variants of the Steiner tree problem in graphs obeying a sharpened β -triangle inequality. A reoptimization algorithm exploits the knowledge of an optimal solution to a problem instance for finding good solutions for a locally modified instance. We show that, in graphs satisfying a sharpened triangle inequality (and even in graphs where edge-costs are restricted to the values 1 and 1+ γ for an arbitrary small γ > 0), Steiner tree reoptimization still is NP-hard for several different types of local modifications, and even APX-hard for some of them. As for the upper bounds, for some local modifications, we design linear-time (1 /2 + β )-approximation algorithms, and even polynomialtime approximation schemes, whereas for metric graphs ( β = 1), none of these reoptimization variants is known to permit a PTAS. As a building block for some of these algorithms, we employ a 2 β -approximation algorithm for the classical Steiner tree problem on such instances, which might be of independent interest since it improves over the previously best known ratio for any β < 1/2 + ln(3)/4 0. 775.

Place, publisher, year, edition, pages
Elsevier, 2011.
Keyword [en]
Steiner tree problem, hardness, reoptimization
National Category
Computer and Information Science Natural Sciences Computer Science
URN: urn:nbn:se:kth:diva-60838DOI: 10.1016/j.jda.2011.03.014ScopusID: 2-s2.0-84856864338OAI: diva2:478009
7th International Conference, CIAC 2010, Rome, Italy, May 26-28, 2010

QC 20150727

Available from: 2012-01-15 Created: 2012-01-15 Last updated: 2015-07-27Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Mömke, Tobias
In the same journal
Journal of Discrete Algorithms
Computer and Information ScienceNatural SciencesComputer Science

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 30 hits
ReferencesLink to record
Permanent link

Direct link