2026-07-24T11:43:31Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:7335 2024-03-06T10:40:06Z ddc:004 open_access

Deterministic Indexing for Packed Strings Bille, Philip Gørtz, Inge Li Skjoldjensen, Frederik Rye suffix tree suffix array deterministic algorithm word packing Given a string S of length n, the classic string indexing problem is to preprocess S into a compact data structure that supports efficient subsequent pattern queries. In the deterministic variant the goal is to solve the string indexing problem without any randomization (at preprocessing time or query time). In the packed variant the strings are stored with several character in a single word, giving us the opportunity to read multiple characters simultaneously. Our main result is a new string index in the deterministic and packed setting. Given a packed string S of length n over an alphabet s, we show how to preprocess S in O(n) (deterministic) time and space O(n) such that given a packed pattern string of length m we can support queries in (deterministic) time O(m/a + log m + log log s), where a = w /log s is the number of characters packed in a word of size w = log n. Our query time is always at least as good as the previous best known bounds and whenever several characters are packed in a word, i.e., log s << w, the query times are faster. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Philip Bille and Inge Li Gørtz and Frederik Rye Skjoldjensen 2017 Is Part Of LIPIcs, Volume 78, 28th Annual Symposium on Combinatorial Pattern Matching (CPM 2017) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.CPM.2017.6 urn:nbn:de:0030-drops-73351 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CPM.2017.6 eng https://creativecommons.org/licenses/by/3.0/legalcode