Testing Quasiperiodicity

Christine Awofeso; Ben Bals; Oded Lachish; Solon P. Pissis

doi:10.1007/978-3-032-05228-5_1

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arXiv · 2508.02231

Testing Quasiperiodicity

Christine Awofeso·Ben Bals·Oded Lachish·Solon P. Pissis

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Abstract

A cover (or quasiperiod) of a string $S$ is a shorter string $C$ such that every position of $S$ is contained in some occurrence of $C$ as a substring. The notion of covers was introduced by Apostolico and Ehrenfeucht over 30 years ago [Theor. Comput. Sci. 1993] and it has received significant attention from the combinatorial pattern matching community. In this note, we show how to efficiently test whether $S$ admits a cover. Our tester can also be translated into a streaming algorithm.

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Christine Awofeso, Ben Bals, Oded Lachish, Solon P. Pissis. 2025-08-04. Testing Quasiperiodicity. https://doi.org/10.1007/978-3-032-05228-5_1

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