Projection Complete Graph Problems Corresponding to a Branching-Program-Based Characterization of the Complexity Classes NC1 ,Land NL

  • Christoph Meinel


The p-projection completeness of some restricted graph accessibility problems for the (nonuniform) complexity classes NC 1 L and NL will be proved by means of branching-program-based characterizations of these classes. A simulation result concerning polynomial-size, bounded-width disjunctive branching programs and polynomial-size, bounded-width usual ones yields that NC 1=L implies L=NL. Some consequences of these results for separating these classes are discussed.


Bran rilE 


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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Christoph Meinel
    • 1
  1. 1.Sektion MathematikHumboldt-UniversitätBerlinGermany

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