DAG-Width and Circumference of Digraphs
نویسندگان
چکیده
منابع مشابه
DAG-width and circumference of digraphs
We prove that every digraph of circumference l has DAG-width at most l and this is best possible. As a consequence of our result we deduce that the k-linkage problem is polynomially solvable for every fixed k in the class of digraphs with bounded circumference. This answers a question posed in [2]. We also prove that the weak k-linkage problem (where we ask for arc-disjoint paths) is polynomial...
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Berwanger et al. show in [BDH+12] that for every graph G of size n and DAGwidth k there is a DAG decomposition of width k of size nO(k). This gives a polynomial time algorithm for determining the DAG-width of a graph for any fixed k. However, if the DAG-width of the graphs from a class is not bounded, such algorithms become exponential. This raises the question whether we can always find a DAG ...
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Hunter and Kreutzer recently introduced the digraph width measure Kelly-width. The measure is based on a vertex elimination process that aims at bounding the out-degree of a vertex during the elimination. We refine the Kelly-width measure by bounding both the out-degree and the in-degree of a vertex. We show that the elimination process and a subgraph characterisation of Kelly-width naturally g...
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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2015
ISSN: 0364-9024
DOI: 10.1002/jgt.21894