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arXiv · 2609.06596

Tunnelling with a reference

Travis Gagie
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Abstract

We show how to modify Baier's tunnelling for the case in which we have a non-repetitive and relatively short reference for a highly repetitive and much longer text. Given a pattern that mostly matches only one substring of the reference, we can use fairly small auxiliary data structures to speed up backward searching with an r-index for the whole text.

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Travis Gagie. 2026-09-06. Tunnelling with a reference. https://arxiv.org/abs/2609.06596

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