A10125. Area of Two Circles' Intersection

You are given two circles. Find the area of their intersection.

The first line contains three integers $x_{1},y_{1},r_{1}$ ( $-10^{9}<=x_{1},y_{1}<=10^{9},1<=r_{1}<=10^{9}$ ) — the position of the center and the radius of the first circle.

The second line contains three integers $x_{2},y_{2},r_{2}$ ( $-10^{9}<=x_{2},y_{2}<=10^{9},1<=r_{2}<=10^{9}$ ) — the position of the center and the radius of the second circle.

Print the area of the intersection of the circles. The answer will be considered correct if the absolute or relative error doesn't exceed $10^{-6}$ .