Abstract
In this paper, we present a method of constructing the maximum prefix-closed subset of a set of –ω-words R defined by a –ω-regular expression. This method is based on constructing a labeled graph called a graph of elementary extensions whose vertices are some –ω-regular subsets of the set R. With every graph vertex, we associate a linear equation over sets of –ω-words. Thus, the graph of elementary extensions determines a system of linear equations. As a result of solving this system of equations, for each vertex of the graph, we obtain the maximum prefix-closed with respect to R subset of the set of –ω-words corresponding to this vertex. The union of such subsets that correspond to all initial vertices of the graph, that is, the vertices constructing the graph starts with, is a maximum prefix-closed subset of the given set R . A method of constructing such a graph is proposed, which we called a method of incomplete intersections. We also present a method to solve the system of equations determined by the graph of elementary extensions.
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Translated from Kibernetyka ta Systemnyi Analiz, No. 6, November–December, 2023, pp. 19–29.
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Chebotarev, A.N. Constructing the Maximum Prefix-Closed Subset for a Set of –ω-Words Defined by a –ω-Regular Expression. Cybern Syst Anal 59, 880–889 (2023). https://doi.org/10.1007/s10559-023-00623-w
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DOI: https://doi.org/10.1007/s10559-023-00623-w