On the State Complexity of Closures and Interiors of Regular Languages with Subwords
نویسندگان
چکیده
We study the closure of regular languages by taking subwords or superwords, provide exact state complexity in the case of unbounded alphabets, and prove new lower bounds in the case of languages over a two-letter alphabet. We also consider the dual interior sets, for which the nondeterministic state complexity has a doubly-exponential upper bound and for which we prove matching doublyexponential lower bounds in the case of unbounded alphabets.
منابع مشابه
On the state complexity of closures and interiors of regular languages with subwords and superwords
The downward and upward closures of a regular language L are obtained by collecting all the subwords and superwords of its elements, respectively. The downward and upward interiors of L are obtained dually by collecting words having all their subwords and superwords in L, respectively. We provide lower and upper bounds on the size of the smallest automata recognizing these closures and interior...
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