Given two rectangles and the coordinates of two points on the diagonals of each rectangle, you have to calculate the area of the intersected part of two rectangles. Its sides are parallel to OX and OY.

**Multiple test cases, please process to the End Of File.** Each test case occupies one line, contains $8$ numbers $x_1,y_1,x_2,y_2,x_3,y_3,x_4,y_4\ (1\le x_i,y_i\le 10000)$. That means the two points on the diagonal of the first rectangle are $(x_1,y_1)$ and $(x_2,y_2)$, and the two points on the diagonal of the second rectangle are $(x_3,y_3)$ and $(x_4,y_4)$.

For each test case, output the area of their intersected part in a single line, accurate up to $2$ decimal places.

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