How to use sorting procedures to minimize DFA

Abstract

In this paper we introduce a new idea, which can be used in minimization of a deterministic finite automaton. Namely, we associate names with states of an automaton and we sort them. We give a new algorithm, its correctness proof, and its proof of execution time bound. This algorithm has time complexity O(n2log n) and can be considered as a direct improvement of Wood's algorithm [6] which has time complexity O(n3), where n is the number of states. Wood's algorithm checks if pairs of states are distinguishable. It is improved by making better use of transitivity. Similarly some other algorithms which check if pairs of states axe distinguishable can be improved using sorting procedures.