Skip to Main content Skip to Navigation
Conference papers

Efficient Seeds Computation Revisited

Abstract : The notion of the cover is a generalization of a period of a string, and there are linear time algorithms for finding the shortest cover. The seed is a more complicated generalization of periodicity, it is a cover of a superstring of a given string, and the shortest seed problem is of much higher algorithmic difficulty. The problem is not well understood, no linear time algorithm is known. In the paper we give linear time algorithms for some of its versions - computing shortest left-seed array, longest left-seed array and checking for seeds of a given length. The algorithm for the last problem is used to compute the seed array of a string (i.e., the shortest seeds for all the prefixes of the string) in O(n²) time. We describe also a simpler alternative algorithm computing efficiently the shortest seeds. As a by-product we obtain an O(n log(n/m)) time algorithm checking if the shortest seed has length at least m and finding the corresponding seed. We also correct some important details missing in the previously known shortest-seed algorithm (Iliopoulos et al., 1996).
Document type :
Conference papers
Complete list of metadata

Cited literature [13 references]  Display  Hide  Download
Contributor : Maxime Crochemore Connect in order to contact the contributor
Submitted on : Wednesday, February 13, 2013 - 10:06:54 AM
Last modification on : Thursday, September 29, 2022 - 2:21:15 PM
Long-term archiving on: : Tuesday, May 14, 2013 - 4:00:24 AM


Files produced by the author(s)


  • HAL Id : hal-00742061, version 1


Michalis Christou, Maxime Crochemore, Costas S. Iliopoulos, Marcin Kubica, Solon P. Pissis, et al.. Efficient Seeds Computation Revisited. CPM, 2011, Palermo, Italy. pp.350-363. ⟨hal-00742061⟩



Record views


Files downloads