Longest Common Separable Pattern between Permutations
نویسندگان
چکیده
In this article, we study the problem of finding the longest common separable pattern between several permutations. We give a polynomial-time algorithm when the number of input permutations is fixed and show that the problem is NP-hard for an arbitrary number of input permutations even if these permutations are separable. On the other hand, we show that the NP-hard problem of finding the longest common pattern between two permutations cannot be approximated better than within a ratio of √ Opt (where Opt is the size of an optimal solution) when taking common patterns belonging to pattern-avoiding classes of permutations.
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ورودعنوان ژورنال:
- CoRR
دوره abs/math/0702109 شماره
صفحات -
تاریخ انتشار 2007