Fast recognition of classes of almost-median graphs
نویسندگان
چکیده
منابع مشابه
Fast recognition of classes of almost-median graphs
In this paper it is shown that a class of almost-median graphs that includes all planar almost-median graphs can be recognized in O(m log n) time, where n denotes the number of vertices and m the number of edges. Moreover, planar almost-median graphs can be recognized in linear time. As a key auxiliary result we prove that all bipartite outerplanar graphs are isometric subgraphs of the hypercub...
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Let M, A, S, and P, be the sets of median graphs, almost-median graphs, semi-median graphs and partial cubes, respectively. Then M ⊂ A ⊂ S ⊂ P. It is proved that a partial cube is almost-median if and only if it contains no convex cycle of length greater that four. This extends the result of Brešar [2] who proved that the same property characterizes almost-median graphs within the class of semi...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2007
ISSN: 0012-365X
DOI: 10.1016/j.disc.2006.07.011