To make things easier, WishingBone decides to put this simple geometry problem at the beginning. Given a triangle, what is the ratio of the area of its inscribed circle to that of its circum circle?

**Input**

9 integers x1 y1 z1 x2 y2 z2 x3 y3 z3 on one line (-1000 <= x, y, z <= 1000), the three coordinates of the triangle. The three coordinates will not appear collinear.

Process to the end of file.

** Output**

One ratio per line, exact to three digits to the right of the decimal point.

** Sample Input**

0 0 0 0 0 1 0 1 0

**Sample Output**

0.172

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