Guarding Rectangular Art Galleries by
نویسندگان
چکیده
Consider a rectangular art gallery divided into n rectangular rooms, such that any two rooms sharing a wall in common have a door connecting them. How many guards need to be stationed in the gallery so as to protect all of the rooms in our gallery? Notice that if a guard is stationed at a door, he will be able to guard two rooms. Our main aim in this paper is to show that Èn/2 ̆ guards are always sufficient to protect all rooms in a rectangular art gallery. Extensions of our result are obtained for non-rectangular galleries and for 3dimensional art galleries. _______________ 1. U. Quebec, Hull, Quebec, Canada. 2. Universidad Autonoma Metropolitana-I, Mexico. 3. Carleton U., Ottawa, Canada. 4. U. Ottawa, Canada. 5. U. Haifa, Israel.
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