A note on module-composed graphs
نویسنده
چکیده
In this paper we consider module-composed graphs, i.e. graphs which can be defined by a sequence of single vertex insertions v1, . . . , vn, such that the neighbourhood of vertex vi, 2 ≤ i ≤ n, forms a module (a homogenous set) of the graph defined by vertices v1, . . . , vi−1. Module composed graphs are HHDS-free and thus homogeneous orderable, weakly chordal, and perfect. Every bipartite distance hereditary graph, every (co-2C4, P4)-free graph and thus every trivially perfect graph is module-composed. We give an O(|VG| ·(|VG|+ |EG|)) time algorithm to decide whether a given graph G is module-composed and construct a corresponding module sequence. For the case of bipartite graphs, module-composed graphs are exactly distance hereditary graphs, which implies simple linear time algorithms for their recognition and construction of a corresponding sequence.
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عنوان ژورنال:
- CoRR
دوره abs/0705.1521 شماره
صفحات -
تاریخ انتشار 2007