More on Deterministic and Nondeterministic Finite Cover Automata

Extended Abstract
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9223)

Abstract

Finite languages are an important sub-regular language family, which were intensively studied during the last two decades in particular from a descriptional complexity perspective. An important contribution to the theory of finite languages are the deterministic and the recently introduced nondeterministic finite cover automata (DFCAs and NFCAs, respectively) as an alternative representation of finite languages by ordinary finite automata. We compare these two types of cover automata from a descriptional complexity point of view, showing that these devices have a lot in common with ordinary finite automata. In particular, we study how to adapt lower bound techniques for nondeterministic finite automata to NFCAs such as, e.g., the biclique edge cover technique, solving an open problem from the literature. Moreover, the trade-off of conversions between DFCAs and NFCAs as well as between finite cover automata and ordinary finite automata are investigated. Finally, we present some results on the average size of finite cover automata.

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Hermann Gruber
    • 1
  • Markus Holzer
    • 2
  • Sebastian Jakobi
    • 2
  1. 1.Knowledgepark AGMunichGermany
  2. 2.Institut für Informatik, Universität GiessenGiessenGermany

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