 
Summary: Approximate Swapped Matching
Amihood Amir Moshe Lewenstein y Ely Porat z
BarIlan University BarIlan University BarIlan University
and and
Georgia Tech Weizmann Institute
Abstract
Let a text string T of n symbols and a pattern string P of m symbols from alphabet be
given. A swapped version P 0 of P is a length m string derived from P by a series of local swaps,
(i.e. p 0
`
p `+1
and p 0
`+1
p `
) where each element can participate in no more than one swap.
The Pattern Matching with Swaps problem is that of nding all locations i of T for which there
exists a swapped version P 0 of P with an exact matching of P 0 in location i of T .
Recently, some eÆcient algorithms were developed for this problem. Their time complexity
is better than the best known algorithms for pattern matching with mismatches. However, the
Approximate Pattern Matching with Swaps problem was not known to be solved faster than the
