Abstract
A string x is an outfix of a string y if there is a string w such that x 1 wx 2=y, where x = x 1 x 2 and a set X of strings is outfix-free if no string in X is an outfix of any other string in X. We examine the outfix-free regular languages. Based on the properties of outfix strings, we develop a polynomial-time algorithm that determines the outfix-freeness of regular languages. We consider two cases: A language is given as a set of strings and a language is given by an acyclic deterministic finite-state automaton. Furthermore, we investigate the prime outfix-free decomposition of outfix-free regular languages and design a linear-time prime outfix-free decomposition algorithm for outfix-free regular languages. We demonstrate the uniqueness of prime outfix-free decomposition.
The authors were supported under the Research Grants Council of Hong Kong Competitive Earmarked Research Grant HKUST6197/01E.
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Han, YS., Wood, D. (2005). Outfix-Free Regular Languages and Prime Outfix-Free Decomposition. In: Van Hung, D., Wirsing, M. (eds) Theoretical Aspects of Computing – ICTAC 2005. ICTAC 2005. Lecture Notes in Computer Science, vol 3722. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11560647_6
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DOI: https://doi.org/10.1007/11560647_6
Publisher Name: Springer, Berlin, Heidelberg
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