Transversals of subtree hypergraphs and the source location problem in digraphs
نویسندگان
چکیده
منابع مشابه
Transversals of subtree hypergraphs and the source location problem in digraphs
A hypergraph H = (V,E) is a subtree hypergraph if there is a tree T on V such that each hyperedge of E induces a subtree of T . To find a minimum size transversal for a subtree hypergraph is, in general, NP-hard. In this paper, we show that if it is possible to decide if a set of vertices W ⊆ V is a transversal in time S(n) ( where n = |V | ), then it is possible to find a minimum size transver...
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ژورنال
عنوان ژورنال: Networks
سال: 2007
ISSN: 0028-3045
DOI: 10.1002/net.20206