|  Optimizing the room usage for students | 
			|  At least one lesson per week has to be in certain classroom | 
			|  We have 3 lessons per week and they shall be in the same classroom | 
			|  Lesson can be only once per week in certain classroom | 
			|  Reducing the room usage | 
			|  GymRoom can only be used 4 days per week(GymRoom has to be free on 3 afternoons) | 
			|  Concentrate groups of lessons into fewer classrooms |