A note on transitive orientations with maximum sets of sources and sinks
نویسندگان
چکیده
Given a transitive orientation ~ G of a comparability graph G, a vertex of G is a source (sink) if it has indegree (outdegree) zero in ~ G, respectively. A source set of G is a subset of vertices formed by sources of some transitive orientation of G. A pair of subsets S; T V (G) is a source-sink pair of G when the vertices of S and T are sources and sinks, respectively, of some transitive orientation of G. We describe algorithms for computing the cardinality of a maximum source set and of a maximum source-sink pair of a comparability graph. In addition, we describe algorithms for nding the corresponding transitive orientations. The algorithms are applications of modular decomposition and are all of linear-time complexity.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 120 شماره
صفحات -
تاریخ انتشار 2002