Permuted pattern matching on multi-track strings

Abstract

We propose a new variant of pattern matching on a multi-set of strings, or multi-tracks, called permuted-matching, that looks for occurrences of a multi-track pattern of length m with M tracks, in a multi-track text of length n with N tracks over Σ. We show that the problem can be solved in O(nNlog|Σ|) time and O(mM + N) space, and further in O(nN) time and space when assuming an integer alphabet. For the case where the number of strings in the text and pattern are equal (full-permuted-matching), we propose a new index structure called the multi-track suffix tree, as well as an O(nN log|Σ|) time and O(nN) space construction algorithm. Using this structure, we can solve the full-permuted-matching problem in O(mN log|Σ| + occ) time for any multi-track pattern of length m with N tracks which occurs occ times. © 2013 Springer-Verlag Berlin Heidelberg.