Abstract
A factor u of a word w is a cover of w if every position in w lies within some occurrence of u in w. A factor u is a seed of w if it is a cover of a superstring of w. Covers and seeds extend the classical notions of periodicity. We introduce a new notion of α-partial seed, that is, a factor covering as a seed at least α positions in a given word. We use the Cover Suffix Tree, introduced recently in the context of α-partial covers (Kociumaka et al, CPM 2013); an \(\mathcal{O}(n\log n)\)-time algorithm constructing such a tree is known. However it appears that partial seeds are more complicated than partial covers—our algorithms require algebraic manipulations of special functions related to edges of the modified Cover Suffix Tree and the border array. We present an algorithm for computing shortest α-partial seeds that works in \(\mathcal{O}(n)\) time if the Cover Suffix Tree is already given.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Apostolico, A., Ehrenfeucht, A.: Efficient detection of quasiperiodicities in strings. Theor. Comput. Sci. 119(2), 247–265 (1993)
Apostolico, A., Farach, M., Iliopoulos, C.S.: Optimal superprimitivity testing for strings. Inf. Process. Lett. 39(1), 17–20 (1991)
Breslauer, D.: An on-line string superprimitivity test. Inf. Process. Lett. 44(6), 345–347 (1992)
Christodoulakis, M., Iliopoulos, C.S., Park, K., Sim, J.S.: Approximate seeds of strings. Journal of Automata, Languages and Combinatorics 10(5/6), 609–626 (2005)
Crochemore, M., Ilie, L., Rytter, W.: Repetitions in strings: Algorithms and combinatorics. Theor. Comput. Sci. 410(50), 5227–5235 (2009)
Crochemore, M., Rytter, W.: Jewels of Stringology. World Scientific (2003)
Iliopoulos, C.S., Moore, D.W.G., Park, K.: Covering a string. Algorithmica 16(3), 288–297 (1996)
Kociumaka, T., Kubica, M., Radoszewski, J., Rytter, W., Waleń, T.: A linear time algorithm for seeds computation. In: Rabani, Y. (ed.) SODA, pp. 1095–1112. SIAM (2012)
Kociumaka, T., Pissis, S.P., Radoszewski, J., Rytter, W., Waleń, T.: Fast algorithm for partial covers in words. In: Fischer, J., Sanders, P. (eds.) CPM 2013. LNCS, vol. 7922, pp. 177–188. Springer, Heidelberg (2013)
Kociumaka, T., Pissis, S.P., Radoszewski, J., Rytter, W., Waleń, T.: Fast algorithm for partial covers in words. In: ArXiv e-prints, arXiv:1401.0163 [cs.DS] (December 2013)
Li, Y., Smyth, W.F.: Computing the cover array in linear time. Algorithmica 32(1), 95–106 (2002)
Moore, D., Smyth, W.F.: An optimal algorithm to compute all the covers of a string. Inf. Process. Lett. 50(5), 239–246 (1994)
Sim, J.S., Park, K., Kim, S., Lee, J.: Finding approximate covers of strings. Journal of Korea Information Science Society 29(1), 16–21 (2002)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer International Publishing Switzerland
About this paper
Cite this paper
Kociumaka, T., Pissis, S.P., Radoszewski, J., Rytter, W., Waleń, T. (2014). Efficient Algorithms for Shortest Partial Seeds in Words. In: Kulikov, A.S., Kuznetsov, S.O., Pevzner, P. (eds) Combinatorial Pattern Matching. CPM 2014. Lecture Notes in Computer Science, vol 8486. Springer, Cham. https://doi.org/10.1007/978-3-319-07566-2_20
Download citation
DOI: https://doi.org/10.1007/978-3-319-07566-2_20
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-07565-5
Online ISBN: 978-3-319-07566-2
eBook Packages: Computer ScienceComputer Science (R0)