Plane Bichromatic Trees of Low Degree
نویسندگان
چکیده
Let R and B be two disjoint sets of points in the plane such that |B| 6 |R|, and no three points of R ∪ B are collinear. We show that the geometric complete bipartite graph K(R,B) contains a non-crossing spanning tree whose maximum degree is at most max { 3, ⌈ |R|−1 |B| ⌉ + 1 } ; this is the best possible upper bound on the maximum degree. This solves an open problem posed by Abellanas et al. at the Graph Drawing Symposium, 1996.
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