Implementation of State Elimination Using Heuristics
نویسندگان
چکیده
State elimination is an intuitive and easy-to-implement algorithm that computes a regular expression from a finite-state automaton (FA). The size of a regular expression from state elimination depends on the state removal sequence. Note that it is very hard to compute the shortest regular expression for a given FA in general and we cannot avoid the exponential blow-up from state elimination. Nevertheless, we notice that we may have a shorter regular expression if we choose a good removal sequence. This observation motivates us to examine heuristics based on the structural properties of an FA and implement state elimination using the heuristics that run in polynomial time. We demonstrate the effectiveness of our algorithm by experiments.
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