A fast and simple O (z log n)-space index for finding approximately longest common substrings
We describe how, given a text T [1..n] and a positive constant ϵ, we can build a simple O (z log n)-space index, where z is the number of phrases in the LZ77 parse of T, such that later, given a pattern P [1..m], in O (m loglog z + polylog (m + z)) time and with high probability we can find a substring of P that occurs in T and whose length is at least a (1 - ϵ)-fraction of the length of a longest common substring of P and T.
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