Large NFA Without Mergeable States
نویسندگان
چکیده
Merging states in finite automata is a main method of reducing the size of the representation of regular languages. The process has been extensively studied for deterministic finite automata (DFA), where the conditions for merging states can be efficiently computed. The matter is more complex in the case of nondeterministic finite automata (NFA), where merging states can be done in different ways, and the cost of detecting mergible states is high. In a recent paper the authors have studied one type of state mergibility and proven that one cannot have an arbitrarily large (in terms of number of states) NFA for a given language such that no states can be merged. In this paper, we study a different type of state mergibility for NFA, which is similar to the state mergibility in a DFA. We prove that there are situations where state merging is impossible for arbitrary large equivalent NFA.
منابع مشابه
Mergible states in large NFA
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تاریخ انتشار 2005