Minimum-link watchman tours
نویسندگان
چکیده
We consider the problem of computing a watchman route in a polygon with holes. We show that the problem of finding a minimum-link watchman route is NP-complete, even if the holes are all convex. The proof is based on showing that the related problem of finding a minimum-link tour on a set of points in the plane is NP-complete. We provide a provably good approximation algorithm that achieves an approximation factor of O(log n).
منابع مشابه
Watchman tours for polygons with holes
A watchman tour in a polygonal domain (for short, polygon) is a closed curve in the polygon such that every point in the polygon is visible from at least one point of the tour. We show that the length of a minimum watchman tour in a polygon P with k holes is O(per(P )+ √ k·diam(P )), where per(P ) and diam(P ) denote the perimeter and the diameter of P , respectively. Apart from the multiplicat...
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 86 شماره
صفحات -
تاریخ انتشار 2003