Kernels in planar digraphs
نویسندگان
چکیده
منابع مشابه
Kernels in planar digraphs
A set S of vertices in a digraph D = (V,A) is a kernel if S is independent and every vertex in V −S has an out-neighbor in S. We show that there exist O(n2 √ k +n)time and O(2 √ k + n)-time algorithms for checking whether a planar digraph D of order n has a kernel with at most k vertices. Moreover, if D has a kernel of size at most k, the algorithms find such a kernel of minimal size.
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ژورنال
عنوان ژورنال: Journal of Computer and System Sciences
سال: 2005
ISSN: 0022-0000
DOI: 10.1016/j.jcss.2005.02.003