int x = 0; //initializing variables
float y = random(255);
float z = random(255);
float a = random(255);

void setup() //setting up the size and background color
{
size(600,200);
background(255);
}

void draw() 
{
 if (mousePressed && (mouseButton == RIGHT)) { //if user uses the right click, it will 
 //generate a random color and draw ellipses.
  fill(x,y,z);
  ellipse(mouseX, mouseY, 20, 20);
 } else if (mousePressed && (mouseButton == LEFT)) { //if user uses the 
 //left click, each ellipose will be drawn in different colors.
  fill(random(255),random(255),random(255));
 ellipse(mouseX, mouseY, 25,25);}} //draws ellipse at the mouse position.