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arXiv · 1404.5244

$\mathrm{Pal}^k$ Is Linear Recognizable Online

Dmitry Kosolobov·Mikhail Rubinchik·Arseny M. Shur
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Abstract

Given a language $L$ that is online recognizable in linear time and space, we construct a linear time and space online recognition algorithm for the language $L\cdot\mathrm{Pal}$, where $\mathrm{Pal}$ is the language of all nonempty palindromes. Hence for every fixed positive $k$, $\mathrm{Pal}^k$ is online recognizable in linear time and space. Thus we solve an open problem posed by Galil and Seiferas in 1978.

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Dmitry Kosolobov, Mikhail Rubinchik, Arseny M. Shur. 2015-01-30. $\mathrm{Pal}^k$ Is Linear Recognizable Online. https://arxiv.org/abs/1404.5244

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