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, specifically 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(2 m +mn+Rm log m) worst case time. On average this drops to O(m