,
Ely Porat
Creative Commons Attribution 4.0 International license
We study the set parameterized matching problem, a generalization of the classical parameterized matching problem introduced by Baker [Baker, 1993; Baker, 1997]. In set parameterized matching, both the pattern and text are sequences where each position contains a set of characters rather than a single character. Two set-strings parameterized match if there exists a bijection between their alphabets that maps one to the other set-wise. Boussidan [Aaron Boussidan, 2025] introduced this problem for the case of equal-length set-strings. We present a randomized algorithm running in O(N + M) time with high probability, where N is the text size and M is the pattern size. Our approach employs a novel three-layer hashing scheme based on Karp-Rabin fingerprinting that addresses the challenges of (1) the size blowup in representations of the problem, (2) set-to-set matching, and (3) the dynamic nature of encodings of text substrings during pattern scanning.
@InProceedings{lewenstein_et_al:LIPIcs.CPM.2026.36,
author = {Lewenstein, Moshe and Porat, Ely},
title = {{Set Parameterized Matching via Multi-Layer Hashing}},
booktitle = {37th Annual Symposium on Combinatorial Pattern Matching (CPM 2026)},
pages = {36:1--36:18},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-420-8},
ISSN = {1868-8969},
year = {2026},
volume = {369},
editor = {Bille, Philip and Prezza, Nicola},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CPM.2026.36},
URN = {urn:nbn:de:0030-drops-259620},
doi = {10.4230/LIPIcs.CPM.2026.36},
annote = {Keywords: Set Parameterized Matching, Pattern Matching, Randomized Algorithms, Hashing, Parameterized Matching}
}