Fast Skew Partition Recognition

  • William S. Kennedy
  • Bruce Reed
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4535)


Chvátal defined a skew partition of a graph G to be a partition of its vertex set into two non-empty parts A and B such that A induces a disconnected subgraph of G and B induces a disconnected subgraph of \(\overline{G}\). Skew partitions are important in the characterization of perfect graphs. De Figuereido et al. presented a polynomial time algorithm which given a graph either finds a skew partition or determines that no such partition exists. It runs in O(n 101) time. We present an algorithm for the same problem which runs in O(n 4 m) time.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • William S. Kennedy
    • 1
  • Bruce Reed
    • 2
  1. 1.Department of Mathematics and StatisticsMcGill UniversityMontréalCanada
  2. 2.School of Computer ScienceMcGill UniversityMontréalCanada

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