Kernels in planar digraphs
نویسندگان
چکیده
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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ورودعنوان ژورنال:
- J. Comput. Syst. Sci.
دوره 71 شماره
صفحات -
تاریخ انتشار 2005