H-coloring degree-bounded (acyclic) digraphs
نویسندگان
چکیده
منابع مشابه
Small H-Coloring Problems for Bounded Degree Digraphs
An NP-complete coloring or homomorphism problem may become polynomial time solvable when restricted to graphs with degrees bounded by a small number, but remain NP-complete if the bound is higher. For instance, 3-colorability of graphs with degrees bounded by 3 can be decided by Brooks’ theorem, while for graphs with degrees bounded by 4, the 3-colorability problem is NP-complete. We investigat...
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An acyclic decomposition of a digraph is a partition of the edges into acyclic subgraphs. Trivially every digraph has an acyclic decomposition into two subgraphs. It is proved that for every integer sX2 every digraph has an acyclic decomposition into s subgraphs such that in each subgraph the outdegree of each vertex v is at most degðvÞ s 1 l m : For all digraphs this degree bound is optimal. r...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2014
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2014.06.014