Brown et al.\ (2025) described a pre-processing step, called k-mer based breaking (KeBaB), that speeds up searching for long maximal exact matches (MEMs) between a pattern P and an indexed repetitive text T. KeBaB produces a set of substrings of P called pseudo-MEMs that often have total length much less than ∣P∣ but are still guaranteed to contain all the MEMs of length at least a fixed parameter k. Brown et al.\ found that KeBaB can be particularly effective when we discard all but the longest pseudo-MEMs -- but then we risk also discarding the longest MEMs! In this paper we show how we can use parse indexing to generate pseudo-MEMs together with lower bounds on the lengths of the longest MEMs they must contain, allowing us to discard short pseudo-MEMs safely.
Cite
@article{arxiv.2605.17574,
title = {Parse indexing for discarding short pseudo-MEMs safely},
author = {Travis Gagie},
journal= {arXiv preprint arXiv:2605.17574},
year = {2026}
}