Bend-Bounded Path Intersection Graphs: Sausages, Noodles, and Waffles on a Grill
نویسندگان
چکیده
In this paper we study properties of intersection graphs of kbend paths in the rectangular grid. A k-bend path is a path with at most k 90 degree turns. The class of graphs representable by intersections of k-bend paths is denoted by Bk-VPG. We show here that for every fixed k, Bk-VPG ( Bk+1-VPG and that recognition of graphs from Bk-VPG is NP-complete even when the input graph is given by a Bk+1-VPG representation. We also show that the class Bk-VPG (for k ≥ 1) is in no inclusion relation with the class of intersection graphs of straight line segments in the plane.
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