Even Triangulations of Planar Set of Points with Steiner Points
نویسنده
چکیده
Let P ⊂ R be a set of n points of which k are interior points. Let us call a triangulation T of P even if all its vertices have even degree, and pseudo-even if at least the k interior vertices have even degree. (Pseudo-) Even triangulations have one nice property; their vertices can be 3-colored, see [2, 3, 4]. Since one can easily check that for some sets of points, such triangulation do not exist, we show an algorithm that constructs a set S of at most ⌊(k + 2)/3⌋ Steiner points (extra points) along with a pseudo-even triangulation T of P ∪ S = V (T ).
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تاریخ انتشار 2010