Enumerate and Expand: Improved Algorithms for Connected Vertex Cover and Tree Cover

  • Daniel Mölle
  • Stefan Richter
  • Peter Rossmanith
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3967)


We present a new method of solving graph problems related to VERTEX COVER by enumerating and expanding appropriate sets of nodes. As an application, we obtain dramatically improved runtime bounds for two variants of the VERTEX COVER problem: In the case of CONNECTED VERTEX COVER, we take the upper bound from O *(6 k ) to O *(3.2361 k ) without large hidden factors. For TREE COVER, we show exactly the same complexity, improving vastly over the previous bound of O *((2k) k ). In the process, faster algorithms for solving subclasses of the Steiner tree problem on graphs are investigated.


Tree Cover Steiner Tree Vertex Cover Graph Class Steiner Tree Problem 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Daniel Mölle
    • 1
  • Stefan Richter
    • 1
  • Peter Rossmanith
    • 1
  1. 1.Dept. of Computer ScienceRWTH Aachen UniversityGermany

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