Guess The Area

#####This is an interactive problem Jonesy has a secret rectangle. The sides of this rectangle are aligned with Cartesian axes $x$ and $y$. Let's denote the coordinates of the lower left corner of the rectangle by ($x$$l$$,y$$l$) and the coordinates of the upper right corner by ($x$$u$$,y$$u$); it is guaranteed that $x$$l$$,y$$l$$,x$$u$$,y$$u$ are non-negative integers. Your task is to find the a