par Kaminski, Marcin 
;Paulusma, Daniël;Thilikos Touloupas, Dimitrios
Référence Journal of discrete algorithms, 9, 3, page (299-306)
Publication Publié, 2011-09
;Paulusma, Daniël;Thilikos Touloupas, Dimitrios Référence Journal of discrete algorithms, 9, 3, page (299-306)
Publication Publié, 2011-09
Article révisé par les pairs
| Résumé : | For every graph H, there exists a polynomial-time algorithm deciding if a planar input graph G can be contracted to H. However, the degree of the polynomial depends on the size of H. We identify a class of graphs C such that for every fixed H C, there exists a linear-time algorithm deciding whether a given planar graph G can be contracted to H. The class C is the closure of planar triangulated graphs under taking of contractions. In fact, we prove that a graph H C if and only if there exists a constant cH such that if the treewidth of a graph is at least cH, it contains H as a contraction. We also provide a characterization of C in terms of minimal forbidden contractions. © 2011 Elsevier B.V. © 2011 Elsevier B.V. All rights reserved. |
