PiApproximation
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This application uses an approximation algorithm to compute pi.

Imagine a circle inscribed in a square with side length 1.
The radius of the circle is 1/2.
The area of a circle of radius r is: pi * r * r
So, the area of our circle of radius 0.5 is: pi * 0.5 * 0.5 = pi/4
Hence, pi is four times the area of the circle.
 
We can approximate the area of the circle by generating random points
in the square of side length 1 and counting how many of them are 
within the circle, i.e. closer than 0.5 to the center.

So, the value of pi is the ratio between the number of inscribed points
and the total number of points, times 4.