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On the Piecewise Complexity of Words and Periodic Words

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SOFSEM 2024: Theory and Practice of Computer Science (SOFSEM 2024)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 14519))

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Abstract

The piecewise complexity h(u) of a word is the minimal length of subwords needed to exactly characterise u. Its piecewise minimality index \(\rho (u)\) is the smallest length k such that u is minimal among its order-k class \([u]_k\) in Simon’s congruence.

We study these two measures and provide efficient algorithms for computing h(u) and \(\rho (u)\). We also provide efficient algorithms for the case where u is a periodic word, of the form \(u=v^n\).

Work supported by IRL ReLaX. J. Veron supported by DIGICOSME ANR-11-LABX-0045.

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Notes

  1. 1.

    In fact \(\delta (u,v)\) is a measure of similarity and not of difference, between u and v. The associated distance is actually \(d(u,v){\mathop {=}\limits ^{\text{ def }}}2^{-\delta (u,v)}\) [SS83].

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Praveen, M., Schnoebelen, P., Veron, J., Vialard, I. (2024). On the Piecewise Complexity of Words and Periodic Words. In: Fernau, H., Gaspers, S., Klasing, R. (eds) SOFSEM 2024: Theory and Practice of Computer Science. SOFSEM 2024. Lecture Notes in Computer Science, vol 14519. Springer, Cham. https://doi.org/10.1007/978-3-031-52113-3_32

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  • DOI: https://doi.org/10.1007/978-3-031-52113-3_32

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