Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4950832 | Information Processing Letters | 2017 | 4 Pages |
Abstract
The match-count problem on strings is a problem of counting the matches of characters for every possible gap of the starting positions between two strings. This problem for strings of lengths m and n (mâ¤n) over an alphabet of size Ï is classically solved in O(Ïnlogâ¡m) time using the algorithm based on the convolution theorem and a fast Fourier transform (FFT). This paper provides a method to reduce the number of computations of the FFT required in the FFT-based algorithm. The algorithm obtained by the proposed method still needs O(Ïnlogâ¡m) time, but the number of required FFT computations is reduced from 3Ï to 2Ï+1. This practical improvement of the processing time is also applicable to other algorithms based on the convolution theorem, including algorithms for the weighted version of the match-count problem.
Related Topics
Physical Sciences and Engineering
Computer Science
Computational Theory and Mathematics
Authors
Kensuke Baba,