let m=0;
let a = 0;
let b= 0;
let n=0;
function setup() {
  createCanvas(400, 400);
  background(220);
  noStroke();
}

function draw() {
  
  
  let x = 20;
  let y = 20;
  let z = 40;
  circle(x+m,y+n,z)
   m= m+1;
  n=n+1; 
  fill(a,b,255)
a=a+1;
b=b+1;
 
}