Computing the partial word avoidability indices of binary patterns
نویسندگان
چکیده
We complete the classification of binary patterns in partial words that was started in earlier publications by proving that the partial word avoidability index of the binary pattern ABABA is two and the one of the binary pattern ABBA is three.
منابع مشابه
Computing the Partial Word Avoidability Indices of Ternary Patterns
We study pattern avoidance in the context of partial words. The problem of classifying the avoidable binary patterns has been solved, so we move on to ternary and more general patterns. Our results, which are based on morphisms (iterated or not), determine all the ternary patterns’ avoidability indices or at least give bounds for them.
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Blanchet-Sadri et al. have shown that Avoidability, or the problem of deciding the avoidability of a finite set of partial words over an alphabet of size k ≥ 2, is NP-hard [Theoret. Comput. Sci. 410 (2009) 968–972]. Building on their work, we analyze in this paper the complexity of natural variations on the problem. While some of them are NP-hard, others are shown to be efficiently decidable. U...
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ورودعنوان ژورنال:
- J. Discrete Algorithms
دوره 23 شماره
صفحات -
تاریخ انتشار 2013