Answer:
Here’s one!
Given [math]R[/math], the radius of the circle.
Let [math]N,D\leftarrow 0[/math]
Repeat until [math]D[/math] is large enough (about 1,000,000)
[math]x,y\leftarrow U[0,1][/math]
If [math]x^2 + y^2\le 1[/math] then [math]N\leftarrow N+1[/math]
[math]D\leftarrow D+1[/math]
[math]P\leftarrow\frac{8NR}{D}[/math]
Return [math]P[/math]
[math]U[0,1][/math] is a uniform random number in the range [math][0,1][/math].
Explanation:
