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Exact Rooted Subtree Matching in Sublinear Time

Luccio, Fabrizio and Mesa Enriquez, Antonio and Olivares Rieumont, P. and Pagli, Linda (2001) Exact Rooted Subtree Matching in Sublinear Time. Technical Report del Dipartimento di Informatica . Università di Pisa, Pisa, IT.

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    The problem of exact subtree matching is the one of deciding if a pattern tree P of m vertices is a subtree of a text tree T of n vertices, m<= n, and, in the affirmative case, finding all the occurrences of P in T. We consider ordered and non-ordered rooted trees with labeled vertices (the case of unlabeled vertices is a special case of this), and show how the problem can be solved in Theta(m + log n) time once a proper data structure is built for T in a preprocessing phase which requires Theta(n) time and space. Regarding T as an immutable text on which several queries are made, P as the contents of one such query, and assuming m=o(n), we can speak of search time sublinear in the size m+n of the overall structure. The number of occurrences of P in T does not appear in the search time because all such occurrences can be directly reconstructed from a constant output information.

    Item Type: Book
    Uncontrolled Keywords: Rooted tree, Subtree matching, Subtree isomorphism, Tree pattern matching, Design of algorithms. Subtree isomorphism, Tree pattern matching, Design of algorithms
    Subjects: Area01 - Scienze matematiche e informatiche > INF/01 - Informatica
    Divisions: Dipartimenti (until 2012) > DIPARTIMENTO DI INFORMATICA
    Depositing User: dott.ssa Sandra Faita
    Date Deposited: 22 Dec 2014 14:23
    Last Modified: 22 Dec 2014 14:23
    URI: http://eprints.adm.unipi.it/id/eprint/2057

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