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arXiv · 0907.0159

The computational complexity of universality problems for prefixes, suffixes, factors, and subwords of regular languages

N. Rampersad·J. Shallit·Z. Xu
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Abstract

In this paper we consider the computational complexity of the following problems: given a DFA or NFA representing a regular language L over a finite alphabet Sigma is the set of all prefixes (resp., suffixes, factors, subwords) of all words of L equal to Sigma*? In the case of testing universality for factors of languages represented by DFA's, we find an interesting connection to Cerny's conjecture on synchronizing words.

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N. Rampersad, J. Shallit, Z. Xu. 2009-07-03. The computational complexity of universality problems for prefixes, suffixes, factors, and subwords of regular languages. https://arxiv.org/abs/0907.0159

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