NC algorithms for comparability graphs, interval graphs, and testing for unique perfect matching

  • Dexter Kozen
  • Umesh V. Vazirani
  • Vijay V. Vazirani
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 206)


Laszlo Lovasz recently posed the following problem: “Is there an NC algorithm for testing if a given graph has a unique perfect matching.” We present such an NC algorithm. The ideas developed may be a step towards obtaining an NC algorithm for determining if a graph has a perfect matching. We also give NC algorithms for obtaining a transitive orientation for a comparability graph, anad an interval representation for an interval graph. These enable us to obtain an NC algorithm for finding a maximum matching in incomparability graphs.


Perfect Match Maximal Clique Interval Graph Comparability Graph Maximum Match 
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 1985

Authors and Affiliations

  • Dexter Kozen
    • 1
  • Umesh V. Vazirani
    • 2
  • Vijay V. Vazirani
    • 3
  1. 1.Cornell UniversityUSA
  2. 2.University of CaliforniaBerkeley
  3. 3.Cornell UniversityUSA

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