Three-coloring triangle-free graphs on surfaces VII. A linear-time algorithm
نویسندگان
چکیده
We give a linear-time algorithm to decide 3-colorability of a trianglefree graph embedded in a fixed surface, and a quadratic-time algorithm to output a 3-coloring in the affirmative case. The algorithms also allow to prescribe the coloring for a bounded number of vertices.
منابع مشابه
Coloring triangle - free graphs on surfaces . Extended
Gimbel and Thomassen asked whether 3-colorability of a triangle-free graph drawn on a fixed surface can be tested in polynomial time. We settle the question by giving a linear-time algorithm for every surface which combined with previous results gives a lineartime algorithm to compute the chromatic number of such graphs. Our algorithm is based on a structure theorem that for a triangle-free gra...
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عنوان ژورنال:
- CoRR
دوره abs/1601.01197 شماره
صفحات -
تاریخ انتشار 2016