Optimal-Time Text Indexing in BWT-runs Bounded Space

  title={Optimal-Time Text Indexing in BWT-runs Bounded Space},
  author={Travis Gagie and Gonzalo Navarro and Nicola Prezza},
  booktitle={ACM-SIAM Symposium on Discrete Algorithms},
Indexing highly repetitive texts --- such as genomic databases, software repositories and versioned text collections --- has become an important problem since the turn of the millennium. A relevant compressibility measure for repetitive texts is $r$, the number of runs in their Burrows-Wheeler Transform (BWT). One of the earliest indexes for repetitive collections, the Run-Length FM-index, used $O(r)$ space and was able to efficiently count the number of occurrences of a pattern of length $m… 

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