An Approximation Algorithm for the Two-Watchman Route in a Simple Polygon
نویسندگان
چکیده
The two-watchman route problem is that of computing a pair of closed tours in an environment so that the two tours together see the whole environment and some length measure on the two tours is minimized. Two standard measures are: the minmax measure, where we want the tours where the longest of them has minimal length, and the minsum measure, where we want the tours for which the sum of their lengths is smallest. It is known that computing the minmax two-watchman route is NP-hard for simple rectilinear polygons and thus also for simple polygons. We exhibit a polynomial time 7.1416-factor approximation algorithm for computing the minmax two-watchman route in simple polygons.
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