Some exercise

That was the firs exercise i did. and while i read the book online, i found that coding.

float r;
float g;
float b;
float a;

float diam;
float x;
float y;

void setup() {
  size(500, 500);
  background(0);
  smooth();
}

void draw() {
  r=random(255);
  g=random(255);
  b=random(255);
  a=random(255);
  diam=random(500);
  x=random(width);
  y=random(height);

  noStroke();
  fill(r, g, b, a);
  ellipse(x, y, diam, diam);
}