Acyclic Automata with Easy-to-Find Short Regular Expressions
نویسندگان
چکیده
Computing short regular expressions equivalent to a given finite automaton is a hard task. In this work we present a class of acyclic automata for which it is easy to find a regular expression that has linear size. We call those automata UDR. A UDR automaton is characterized by properties of its underlying digraph. We present a characterisation theorem and an efficient algorithm to determine if an acyclic automaton is UDR. This algorithm can be adapted to compute a short regular expression equivalent to a given UDR automaton.
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تاریخ انتشار 2005