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computational complexity

, Volume 5, Issue 2, pp 155–166 | Cite as

A note on logspace optimization

  • Carme Àlvarez
  • Birgit Jenner
Article

Abstract

We show that computing iterated multiplication of word matrices over {0,1}*, using the operations maximum and concatenation, is complete for the class optL of logspace optimization functions. The same problem for word matrices over {1}* is complete for the class FNL of nondeterministic logspace functions. Improving previously obtained results, we furthermore place the class optL in AC1, and characterize FNL by restricted logspace optimization functions.

Key words

Complexity classes nondeterministic logspace optimization iterated multiplication 

Subject classifications

68Q15 68Q25 

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Copyright information

© Birkhäuser Verlag 1995

Authors and Affiliations

  • Carme Àlvarez
    • 1
  • Birgit Jenner
    • 2
  1. 1.Dept. Llenguatges i Sistemes InformàticsUniversitat Politècnica de CatalunyaBarcelonaSpain
  2. 2.Fakultät für InformatikUniversität TübingenTübingenGermany

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