Definability by Weakly Deterministic Regular Expressions with Counters is Decidable
نویسندگان
چکیده
We show that weakly deterministic regular expressions with counters (WDREs) —as they are used in XML Schema— are at most exponentially larger than equivalent DFAs. As a consequence, the problem, whether a given DFA is equivalent to any WDRE, is decidable in EXPSPACE.
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