let speedX = 2;

​

​

function setup() {

  createCanvas(400, 400);

}

​

function draw() {

  background(220);

  stroke(200)

  strokeWeight(6)

  noFill()

  ellipse(x, 200, 169, 150);

  x += speedX; 

  if (x>width){

    speedX = -1

  }

​

}