Finding a subdivision of a digraph
نویسندگان
چکیده
We consider the following problem for oriented graphs and digraphs: Given a directed graphD, does it contain a subdivision of a prescribed digraph F? We give a number of examples of polynomial instances, several NP-completeness proofs as well as a number of conjectures and open problems. Key-words: NP-completeness, 2-linkage, flows, DAG and handle decompositions. ∗ Department of Mathematics and Computer Science, University of Southern Denmark, Odense DK-5230, Denmark (email: [email protected]). † Most of this work was done while J. Bang-Jensen visited Projet Mascotte, I3S (CNRS, UNSA) and INRIA, Sophia Antipolis whose hospitality and financial support is gratefully acknowledged. ‡ Projet Mascotte, I3S (CNRS, UNSA) and INRIA, Sophia Antipolis. Partly supported by ANR Blanc AGAPE and CAPES/Brazil. (email:[frederic.havet, karol.maia]@inria.fr) Trouver une subdivision d’un digraphe Résumé : Nous considérons le problème suivant: étant donné un graphe orientéD, contient-il une subdivision d’un digraphe fixé F? Nous donnons des exemples d’instances polynomiales, plusieurs preuves de NP-complétude ainsi qu’un certain nombre de conjectures et de problèmes ouverts. Mots-clés : NP-complétude, 2-linkage, Flots, décompositions en DAG et en oreilles. Finding a subdivision of a digraph 3
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 562 شماره
صفحات -
تاریخ انتشار 2015