Vertices belonging to all or to no minimum double dominating sets in trees
نویسندگان
چکیده
In a graph G = (V, E) , a vertex dominates itself and all its neighbors. A double dominating set of G is a dominating set that dominates every vertex of G at least twice. In this paper, we characterize vertices that are in all or in no minimum double dominating sets in trees.
منابع مشابه
Vertices Belonging to All or to No Minimum Locating Dominating Sets of Trees
A set D of vertices in a graph G is a locating-dominating set if for every two vertices u, v of G \ D the sets N(u) ∩ D and N(v) ∩ D are non-empty and different. In this paper, we characterize vertices that are in all or in no minimum locating dominating sets in trees. The characterization guarantees that the γL-excellent tree can be recognized in a polynomial time.
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