Optimally Edge-Colouring Outerplanar Graphs is in NC
نویسندگان
چکیده
We prove that every outerplanar graph can be optimally edge-coloured in polylogarithmic time using a polynomial number of processors on a parallel random access machine without write conflicts (P-RAM).
منابع مشابه
Strong edge-colouring and induced matchings
A strong edge-colouring of a graph G is a proper edge-colouring such that every path of three edges uses three colours. An induced matching of a graph G is a subset I of edges of G such that the graph induced by the endpoints of I is a matching. In this paper, we prove the NP-completeness of strong 4, 5, and 6-edge-colouring and maximum induced matching in some subclasses of subcubic triangle-f...
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An edge-colouring is strong if every colour class is an induced matching. In this work we give a formulae that determines either the optimal or the optimal plus one strong chromatic index of bipartite outerplanar graphs. Further, we give an improved upper bound for any outerplanar graph which is close to optimal. All our proofs yield efficient algorithms to construct such colourings.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 71 شماره
صفحات -
تاریخ انتشار 1990