Pfaffian orientations, 0/1 permanents, and even cycles in directed graphs

  • Vijay V. Vazirani
  • Mihalis Yannakakis
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 317)


The following issues in computational complexity remain imprecisely understood: the striking difference in the complexities of computing the permanent and determinant of a matrix despite their similar looking formulae, the complexity of checking if a directed graph contains an even length cycle, and the complexity of computing the number of perfect matchings in a graph using Pfaffian orientations. Via polynomial time equivalences, we show interrelationships among these issues.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • Vijay V. Vazirani
    • 1
  • Mihalis Yannakakis
    • 2
  1. 1.Computer Science DepartmentCornell UniversityUSA
  2. 2.AT&T Bell LabsMurray Hill

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