Querying Regular Languages over Sliding Windows
نویسندگان
چکیده
We study the space complexity of querying regular languages over data streams in the sliding window model. The algorithm has to answer at any point of time whether the content of the sliding window belongs to a fixed regular language. A trichotomy is shown: For every regular language the optimal space requirement is either in Θ(n), Θ(logn), or constant, where n is the size of the sliding window. 1998 ACM Subject Classification F.2.2 Nonnumerical Algorithms and Problems, F.4.3 Formal Languages
منابع مشابه
Querying languages over sliding windows
We study the space complexity of querying languages over data streams in the sliding window model. The algorithm has to answer at any point of time whether the content of the sliding window belongs to a fixed regular language. For regular languages, a trichotomy is shown: For every regular language the optimal space requirement is asymptotically either constant, logarithmic, or linear in the si...
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