On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs
Clique-Helly and hereditary clique-Helly graphs are polynomial-time recognizable. Recently, we presented a proof that the clique graph recognition problem is NP-complete [L. Alcón, L. Faria, C.M.H. de Figueiredo, M. Gutierrez, Clique graph recognition is NP-complete, in: Proc. WG 2006, in: Lecture N...
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Formato: | Articulo |
Lenguaje: | Inglés |
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2010
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Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/82445 |
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I19-R120-10915-82445 |
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record_format |
dspace |
institution |
Universidad Nacional de La Plata |
institution_str |
I-19 |
repository_str |
R-120 |
collection |
SEDICI (UNLP) |
language |
Inglés |
topic |
Matemática Approximation algorithms Clique graphs Clique-Helly graphs Hereditary clique-Helly graphs Max SNP-hard NP-complete Clique graphs |
spellingShingle |
Matemática Approximation algorithms Clique graphs Clique-Helly graphs Hereditary clique-Helly graphs Max SNP-hard NP-complete Clique graphs Alcón, Liliana Graciela Faria, L. Figueiredo, C. M. H. de Gutiérrez, Marisa On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
topic_facet |
Matemática Approximation algorithms Clique graphs Clique-Helly graphs Hereditary clique-Helly graphs Max SNP-hard NP-complete Clique graphs |
description |
Clique-Helly and hereditary clique-Helly graphs are polynomial-time recognizable. Recently, we presented a proof that the clique graph recognition problem is NP-complete [L. Alcón, L. Faria, C.M.H. de Figueiredo, M. Gutierrez, Clique graph recognition is NP-complete, in: Proc. WG 2006, in: Lecture Notes in Comput. Sci., vol. 4271, Springer, 2006, pp. 269-277]. In this work, we consider the decision problems: given a graph G = (V, E) and an integer k ≥ 0, we ask whether there exists a subset V ′ ⊆ V with | V ′ | ≥ k such that the induced subgraph G [V ′ ] of G is, variously, a clique, clique-Helly or hereditary clique-Helly graph. The first problem is clearly NP-complete, from the above reference; we prove that the other two decision problems mentioned are NP-complete, even for maximum degree 6 planar graphs. We consider the corresponding maximization problems of finding a maximum induced subgraph that is, respectively, clique, clique-Helly or hereditary clique-Helly. We show that these problems are Max SNP-hard, even for maximum degree 6 graphs. We show a general polynomial-time frac(1, Δ + 1)-approximation algorithm for these problems when restricted to graphs with fixed maximum degree Δ. We generalize these results to other graph classes. We exhibit a polynomial 6-approximation algorithm to minimize the number of vertices to be removed in order to obtain a hereditary clique-Helly subgraph. |
format |
Articulo Articulo |
author |
Alcón, Liliana Graciela Faria, L. Figueiredo, C. M. H. de Gutiérrez, Marisa |
author_facet |
Alcón, Liliana Graciela Faria, L. Figueiredo, C. M. H. de Gutiérrez, Marisa |
author_sort |
Alcón, Liliana Graciela |
title |
On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
title_short |
On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
title_full |
On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
title_fullStr |
On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
title_full_unstemmed |
On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs |
title_sort |
on maximizing clique, clique-helly and hereditary clique-helly induced subgraphs |
publishDate |
2010 |
url |
http://sedici.unlp.edu.ar/handle/10915/82445 |
work_keys_str_mv |
AT alconlilianagraciela onmaximizingcliquecliquehellyandhereditarycliquehellyinducedsubgraphs AT farial onmaximizingcliquecliquehellyandhereditarycliquehellyinducedsubgraphs AT figueiredocmhde onmaximizingcliquecliquehellyandhereditarycliquehellyinducedsubgraphs AT gutierrezmarisa onmaximizingcliquecliquehellyandhereditarycliquehellyinducedsubgraphs |
bdutipo_str |
Repositorios |
_version_ |
1764820488288206849 |