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Data structure lower bounds for document indexing problems. (English) Zbl 1388.68026
Chatzigiannakis, Ioannis (ed.) et al., 43rd international colloquium on automata, languages, and programming, ICALP 2016, Rome, Italy, July 12–15, 2016. Proceedings. Wadern: Schloss Dagstuhl – Leibniz Zentrum für Informatik (ISBN 978-3-95977-013-2). LIPIcs – Leibniz International Proceedings in Informatics 55, Article 93, 15 p. (2016).
Summary: We study data structure problems related to document indexing and pattern matching queries and our main contribution is to show that the pointer machine model of computation can be extremely useful in proving high and unconditional lower bounds that cannot be obtained in any other known model of computation with the current techniques. Often our lower bounds match the known space-query time trade-off curve and in fact for all the problems considered, there is a very good and reasonable match between our lower bounds and the known upper bounds, at least for some choice of input parameters.
The problems that we consider are set intersection queries (both the reporting variant and the semi-group counting variant), indexing a set of documents for two-pattern queries, or forbidden-pattern queries, or queries with wild-cards, and indexing an input set of gapped-patterns (or two-patterns) to find those matching a document given at the query time.
For the entire collection see [Zbl 1351.68012].

68P05 Data structures
68Q05 Models of computation (Turing machines, etc.) (MSC2010)
68Q17 Computational difficulty of problems (lower bounds, completeness, difficulty of approximation, etc.)
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