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String Covers of a Tree

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String Processing and Information Retrieval (SPIRE 2021)

Abstract

We consider covering labeled trees by a collection of paths with the same string label, called a (string) cover of a tree. We show how to compute all covers of a directed (rooted) labeled tree in \({\mathcal {O}}(n \log n/\log \log n)\) time and all covers of an undirected labeled tree in \({\mathcal {O}}(n^2)\) time and space or in \({\mathcal {O}}(n^2 \log n)\) time and \({\mathcal {O}}(n)\) space. We also show several essential differences between covers in standard strings and covers in trees.

Work supported by the Polish National Science Center, grant no. 2018/31/D/ST6/03991.

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Radoszewski, J., Rytter, W., Straszyński, J., Waleń, T., Zuba, W. (2021). String Covers of a Tree. In: Lecroq, T., Touzet, H. (eds) String Processing and Information Retrieval. SPIRE 2021. Lecture Notes in Computer Science(), vol 12944. Springer, Cham. https://doi.org/10.1007/978-3-030-86692-1_7

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  • DOI: https://doi.org/10.1007/978-3-030-86692-1_7

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