The 2-Tuple Domination Problem on Trapezoid Graphs
نویسندگان
چکیده
Given a simple graph G = (V, E) and a fixed positive integer k. In a graph G, a vertex is said to dominate itself and all of its neighbors. A set D ⊆ V is called a k-tuple dominating set if every vertex in V is dominated by at least k vertices of D. The k-tuple domination problem is to find a minimum cardinality k-tuple dominating set. This problem is NP-complete for general graphs. In this paper, the same problem restricted to a class of graphs called trapezoid graphs is considered. In particular, we presented an O(n)-time algorithm to solve the 2-tuple domination problem on trapezoid graphs.
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