Approximation to the Minimum Rooted Star Cover Problem

  • Wenbo Zhao
  • Peng Zhang
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4484)


In this paper, we study the following minimum rooted star cover problem: given a complete graph G = (V, E) with a length function l: E →ℤ +  that satisfies the triangle inequality, a designated root vertex r ∈ V, and a length bound D, the objective is to find a minimum cardinality set of rooted stars, that covers all vertices in V such that the length of each rooted star is at most D, where a rooted star is a subset of E having a common center s ∈ V and containing the edge (r, s). This problem is NP-complete and we present a constant ratio approximation algorithm for this problem.


Minimum Rooted Star Cover Approximation Algorithm 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Wenbo Zhao
    • 1
    • 2
  • Peng Zhang
    • 1
    • 2
  1. 1.State Key Lab. of Computer Science, Institute of Software, Chinese Academy of Sciences, P.O.Box 8718, Beijing, 100080China
  2. 2.Graduate University of Chinese Academy of Sciences, BeijingChina

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