Some Remarks On Global Total Domination In Graphs∗
نویسندگان
چکیده
A subset S of vertices in a graph G is a global total dominating set, or just GTDS, if S is a total dominating set of both G and G. The global total domination number γgt(G) of G is the minimum cardinality of a GTDS of G. In this paper, we show that the decision problem for γgt(G) is NP-complete, and then characterize graphs G of order n with γgt(G) = n− 1.
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