LOGO#2026
Company VENICE has asked you to design a new logo for its products: modern PCs assembled from the best components selected from world markets. The company wants the background of the logo to consist of two overlapping squares. The squares themselves should be black, and their intersection should be white. One example of the logo background can be seen in the picture. You are required to calculate the area of the black parts of the logo.
Note: The squares in the logo may intersect in any manner; in particular, they may be nested within each other or just touch.
The input consists of two lines. Each line contains four real numbers: x_1, y_1, x_2, y_2 — the coordinates of two opposite vertices of a square. Here, -1000.0 < x_1, y_1, x_2, y_2 < 1000.0.
Print a single real number — the area of the shape to be painted, with an absolute or relative error of 10^{-5}.
Example 1