Max-leaves spanning tree is APX-hard for cubic graphs
نویسنده
چکیده
We consider the problem of finding a spanning tree with maximum number of leaves (MaxLeaf). A 2-approximation algorithm is known for this problem, and a 3/2-approximation algorithm when restricted to graphs where every vertex has degree 3 (cubic graphs). MaxLeaf is known to be APX-hard in general, and NP-hard for cubic graphs. We show that the problem is also APX-hard for cubic graphs. The APX-hardness of the related problem Minimum Connected Dominating Set for cubic graphs follows.
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ورودعنوان ژورنال:
- J. Discrete Algorithms
دوره 12 شماره
صفحات -
تاریخ انتشار 2012