y = 0;

​

Npoints_incirc = 0.0;

Npoints = 0.0;

​

function draw() {

   x = random(-radius,radius);

   y = random(-radius,radius);  

     if ( x*x + y*y < radius*radius) {  

       Npoints_incirc += 1.0;

     drawPointGray(x,y);

   } else {

     drawPointBlack(x,y);

   }

  Npoints += 1.0;

  print(4.0*Npoints_incirc/Npoints);

}