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arXiv · 1403.2431

A Subquadratic Algorithm for Minimum Palindromic Factorization

Gabriele Fici·Travis Gagie·Juha Kärkkäinen·Dominik Kempa
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Abstract

We give an $\mathcal{O}(n \log n)$-time, $\mathcal{O}(n)$-space algorithm for factoring a string into the minimum number of palindromic substrings. That is, given a string $S [1..n]$, in $\mathcal{O}(n \log n)$ time our algorithm returns the minimum number of palindromes $S_1,\ldots, S_\ell$ such that $S = S_1 \cdots S_\ell$. We also show that the time complexity is $\mathcal{O}(n)$ on average and $\Omega(n\log n)$ in the worst case. The last result is based on a characterization of the palindromic structure of Zimin words.

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Gabriele Fici, Travis Gagie, Juha Kärkkäinen, Dominik Kempa. 2014-03-10. A Subquadratic Algorithm for Minimum Palindromic Factorization. https://doi.org/10.1016/j.jda.2014.08.001

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