createCanvas(400, 400);

}

​

function draw() {

  background(0);

  var x=0

  //I had to add = after x< to make the circles go all the way to the end

  while (x<=width){

    fill(0,200,255);

    ellipse(x,100,25,25);

    x=x+50

  }

  // x=x+50 can be written as x+=50 and x=x+1 can be written as x++

  // for and while are similar, but for can be written all in 1 line

  for (var x=0; x<=width; x+=50){

    fill(255,0,200);

    ellipse(x,300,25,25);

  }

}