public double getCost(AState state1, AState state2)
	{
		int x = Math.abs(state2.getX() - state1.getX());
		int y = Math.abs(state2.getY() - state1.getY());
		
		if(x > 1 || y > 1) return -1;
		else if(x == 1 && y == 1) return Math.sqrt(2);
		else if(x == 1 || y == 1) return 1;
		else return 0;
	}