Monotone Boolean dualization is in co-NP[log2n]
نویسندگان
چکیده
In 1996, Fredman and Khachiyan [J. Algorithms 21 (1996) 618–628] presented a remarkable algorithm for the problem of checking the duality of a pair of monotone Boolean expressions in disjunctive normal form. Their algorithm runs in no(logn) time, thus giving evidence that the problem lies in an intermediate class between P and co-NP. In this paper we show that a modified version of their algorithm requires deterministic polynomial time plus O(log2 n) nondeterministic guesses, thus placing the problem in the class co-NP[log2 n]. Our nondeterministic version has also the advantage of having a simpler analysis than the deterministic one. 2002 Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Inf. Process. Lett.
دوره 85 شماره
صفحات -
تاریخ انتشار 2003