Given a string T of length n over an alphabet Σ ⊂ {1,2,…,n^{𝒪(1)}} of size σ, we are to preprocess T so that given a range [i,j], we can return a representation of a shortest string over Σ that is absent in the fragment T[i]⋯ T[j] of T. For any positive integer k ∈ [1,log log_σ n], we present an 𝒪((n/k)⋅ log log_σ n)-size data structure, which can be constructed in 𝒪(nlog_σ n) time, and answers queries in time 𝒪(log log_σ k).
@InProceedings{badkobeh_et_al:LIPIcs.CPM.2021.6, author = {Badkobeh, Golnaz and Charalampopoulos, Panagiotis and Pissis, Solon P.}, title = {{Internal Shortest Absent Word Queries}}, booktitle = {32nd Annual Symposium on Combinatorial Pattern Matching (CPM 2021)}, pages = {6:1--6:18}, series = {Leibniz International Proceedings in Informatics (LIPIcs)}, ISBN = {978-3-95977-186-3}, ISSN = {1868-8969}, year = {2021}, volume = {191}, editor = {Gawrychowski, Pawe{\l} and Starikovskaya, Tatiana}, publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik}, address = {Dagstuhl, Germany}, URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CPM.2021.6}, URN = {urn:nbn:de:0030-drops-139570}, doi = {10.4230/LIPIcs.CPM.2021.6}, annote = {Keywords: string algorithms, internal queries, shortest absent word, bit parallelism} }
Feedback for Dagstuhl Publishing