Minimal Cover-Automata for Finite Languages

  • Cezar Câmpeanu
  • Nicolae Sântean
  • Sheng Yu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1660)


A cover-automaton A of a finite language L ⊆ Σ* is a finite automaton that accepts all words in L and possibly other words that are longer than any word in L. A minimal deterministic cover automaton of a finite language L usually has a smaller size than a minimal DFA that accept L. Thus, cover automata can be used to reduce the size of the representations of finite languages in practice. In this paper, we describe an efficient algorithm that, for a given DFA accepting a finite language, constructs a minimal deterministic finite coverautomaton of the language. We also give algorithms for the boolean operations on deterministic cover automata, i.e., on the finite languages they represent.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Cezar Câmpeanu
    • 1
  • Nicolae Sântean
    • 1
  • Sheng Yu
    • 1
  1. 1.Department of Computer ScienceUniversity of Western OntarioLondonCanada

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