Cover Complexity of Finite Languages

  • Stefan Hetzl
  • Simon WolfsteinerEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10952)


We consider the notion of cover complexity of finite languages on three different levels of abstraction. For arbitrary cover complexity measures, we give a characterisation of the situations in which they collapse to a bounded complexity measure. Moreover, we show for a restricted class of context-free grammars that its grammatical cover complexity measure w.r.t. a finite language L is unbounded and that the cover complexity of L can be computed from the exact complexities of a finite number of covers \(L' \supseteq L\). We also investigate upper and lower bounds on the grammatical cover complexity of the language operations intersection, union, and concatenation on finite languages for several different types of context-free grammars.



The authors would like to thank Markus Holzer and the anonymous reviewers for several useful comments and suggestions concerning the results in this paper.


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© IFIP International Federation for Information Processing 2018

Authors and Affiliations

  1. 1.Institute of Discrete Mathematics and GeometryTU WienWienAustria

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