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arXiv · 2606.18696

Compact multi-text index for circular Cartesian tree matching

Roman Pauli·Eric Osterkamp·Dominik Köppl
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Abstract

Cartesian tree matching (CTM) is a structural pattern matching approach that identifies sequences with the same Cartesian tree topology, making it suitable for data with natural variability where exact comparisons carry little semantic meaning. While theoretical algorithms for CTM have been studied extensively, systematic empirical evaluations of practical implementations remain rare. This article presents an implementation of the Cartesian Extended Burrows-Wheeler Transform (ceBWT), a BWT-based index structure for CTM. The implementation supports both a dynamically extendable and a statically compressed index variant.

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Roman Pauli, Eric Osterkamp, Dominik Köppl. 2026-06-17. Compact multi-text index for circular Cartesian tree matching. https://arxiv.org/abs/2606.18696

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