Complexity classes with complete problems between P and NP-C

  • Carme Àlvarez
  • Josep Díaz
  • Jacobo Torán
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 380)


We study certain language classes located between P and NP that are defined by polynomial time machines with bounded amount of nondeterminism. We observe that these classes have complete problems, and find characterizations of the classes using robust machines with bounded access to the oracle, and in terms of nondeterministic complexity classes with polylog running time. We also study the relationship of these classes to P and NP.


Polynomial Time Turing Machine Computation Path Complete Problem Oracle Query 
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 1989

Authors and Affiliations

  • Carme Àlvarez
    • 1
  • Josep Díaz
    • 1
  • Jacobo Torán
    • 1
  1. 1.Departament de Llenguatges i Sistemes InformàticsUniversitat Politècnica de CatalunyaBarcelona

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