function setup() {
  createCanvas(400, 400);
  background(220);

  // test with different parameters
  body(240, 100, 80, 3);
  head(200, 100, 100);

  body(220, 200, 40, 6);
  head(200, 200, 50);

  body(204, 300, 8, 20);
  head(200, 300, 10);
}

function body(x, y, diam, repeat) {
  invert = 0;

  for (i = 0; i < repeat; i++) {
    if (invert == 0) {
      fill("rgb(0,200,0)");
      invert = 1;
    } else {
      fill("rgb(0,255,0)");
      invert = 0;
    }

    // shift x a bit for body part, make is a chain
    circle(x + i * diam * 0.8, y, diam);
  }
}

// x, y: the center of the head
// diam: the diameter of the head
function head(x, y, diam) {
  // [Your Code Here]

  fill("rgb(0,255,0)");
  circle(x, y, diam);

  // eyes
  x_factor = diam * 0.15;
  y_factor = diam * 0.1;
  fill("rgb(0,0,0)");
  circle(x - x_factor, y - y_factor, x_factor);
  fill("rgb(0,0,0)");
  circle(x + x_factor, y - y_factor, x_factor);

  // mouths
  noFill();
  arc(x, y + y_factor, x_factor * 2, x_factor * 2, 0, PI);
}