public void remove(Course[][] courses)
	{
		System.out.println();
		System.out.print("Enter semester to remove: ");
		int semester = scan.nextInt();
		System.out.print("Enter course to remove: ");
		int course = scan.nextInt();
		if( semester > courses.length || course > courses[semester].length || courses[semester][course] == null)
		{
			System.out.println("Invalid location");
		}
		else
		{
			courses[semester][course] = null;
		}
	}