Forbidden Patterns
نویسندگان
چکیده
We consider the problem of indexing a collection of documents (a.k.a. strings) of total length n such that the following kind of queries are supported: given two patterns P and P−, list all nmatch documents containing P but not P−. This is a natural extension of the classic problem of document listing as considered by Muthukrishnan [SODA’02], where only the positive pattern P is given. Our main solution is an index of size O(n) bits that supports queries in O(|P| + |P−|+ nmatch + √ n) time.
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تاریخ انتشار 2012