Deciding 4-colorability of planar triangulations
نویسنده
چکیده
We show, without using the Four Color Theorem, that for each planar triangulation, the number of its proper vertex colorings by 4 colors is a determinant and thus can be calculated in a polynomial time. In particular, we can efficiently decide if the number is non-zero.
منابع مشابه
3-Colorability of Pseudo-Triangulations
Deciding 3-colorability for general plane graphs is known to be an NP-complete problem. However, for certain classes of plane graphs, like triangulations, polynomial time algorithms exist. We consider the family of pseudo-triangulations (a generalization of triangulations) and prove NP-completeness for this class. The complexity status does not change if the maximum face-degree is bounded to fo...
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ورودعنوان ژورنال:
- CoRR
دوره abs/1505.03962 شماره
صفحات -
تاریخ انتشار 2015