Longest \(\alpha \)-Gapped Repeat and Palindrome

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9210)


We propose an efficient algorithm finding, for a word w and an integer \(\alpha >0\), the longest word u such that w has a factor uvu, with \(|uv|\le \alpha |u|\) (i.e., the longest \(\alpha \)-gapped repeat of w). Our algorithm runs in \({\mathcal O}(\alpha n)\) time. Moreover, it can be easily adapted to find the longest u such that w has a factor \(u^Rvu\), with \(|uv|\le \alpha |u|\) (i.e., the longest \(\alpha \)-gapped palindrome), again in \({\mathcal O}(\alpha n)\) time.


Basic Factor Suffix Tree Input Word Suffix Array Common Prefix 
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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Institute of InformaticsUniversity of WarsawWarsawPoland
  2. 2.Department of Computer ScienceKiel UniversityKielGermany

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