A Constant-Factor Approximation Algorithm for Optimal 1.5D Terrain Guarding
نویسندگان
چکیده
We present the first constant-factor approximation algorithm for a non-trivial instance of the optimal guarding (coverage) problem in polygons. In particular, we give an O(1)-approximation algorithm for placing the fewest point guards on a 1.5D terrain, so that every point of the terrain is seen by at least one guard. While polylogarithmic-factor approximations follow from set cover results, our new results exploit geometric structure of terrains to obtain a substantially improved approximation algorithm.
منابع مشابه
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عنوان ژورنال:
- SIAM J. Comput.
دوره 36 شماره
صفحات -
تاریخ انتشار 2007