On the approximability and exact algorithms for vector domination and related problems in graphs

نویسندگان

  • Ferdinando Cicalese
  • Martin Milanic
  • Ugo Vaccaro
چکیده

We consider two graph optimization problems called vector domination and total vector domination. In vector domination one seeks a small subset S of vertices of a graph such that any vertex outside S has a prescribed number of neighbors in S. In total domination, the requirement is extended to all vertices of the graph. We prove that these problems cannot be approximated to within a factor of c logn, for suitable constant c, unless every problem in NP is solvable in slightly super-polynomial time. We also show that two natural greedy strategies have approximation factor O(log∆(G)), where ∆(G) is the maximum degree of the graph G. We also provide exact polynomial time algorithms for several classes of graphs. Our results extend and unify several results previously known in the literature.

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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 161  شماره 

صفحات  -

تاریخ انتشار 2013