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CPM
2001
Springer

Regular Expression Searching over Ziv-Lempel Compressed Text

14 years 3 months ago
Regular Expression Searching over Ziv-Lempel Compressed Text
We present a solution to the problem of regular expression searching on compressed text. The format we choose is the Ziv-Lempel family, speci cally the LZ78 and LZW variants. Given a text of length u compressed into length n, and a pattern of length m, we report all the R occurrences of the pattern in the text in O(2m + mn + Rmlogm) worst case time. On average this drops to O(m2 + (n + R)logm) or O(m2 + n+ Ru=n) for most regular expressions. This is the rst nontrivial result for this problem. The experimental results show that our compressed search algorithm needs half the time necessary for decompression plus searching, which is currently the only alternative.
Gonzalo Navarro
Added 28 Jul 2010
Updated 28 Jul 2010
Type Conference
Year 2001
Where CPM
Authors Gonzalo Navarro
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