int x = 100;
int y = 100;
int w = 60;
int h = 60; 
int eyeSize = 16;
int speed = 1;

void setup() {
  
  size(200, 200);
  smooth();
  
}

void draw() {
  
  //Change the x location of Zoog by speed
  x = x + speed; 
  
  //If we've reached an edge, reverse speed (i.e. mulitply it by -1)
  //(Note if speed is a + number, square moves to the right, - to the left
  if ((x > width) || (x < 0)) {
    speed = speed * -1;
  }
  
  background(255); //Draw a white background
  
  //Set ellipses and rects to CENTER mode
  ellipseMode(CENTER);
  rectMode(CENTER);
  
  //Draw Zoog's arms with a for loop
  for (int i = y+5; i < y + h; i+=10) {
    stroke(0);
    line(x-w/3, i, x+w/3, i);
  }
  
  //Draw Zoog's body
  stroke(0);
  fill(175);
  rect(x, y, w/6, h*2);
  
  //Draw Zoog's head
  fill(255);
  ellipse(x, y-h/2, w, h);
  
  //Draw Zoog's eyes
  fill(0);
  ellipse(x-w/3, y-h/2, eyeSize, eyeSize*2);
  ellipse(x+w/3, y-h/2, eyeSize, eyeSize*2);
  
  //Draw Zoog's legs
  stroke(0);
  line(x-w/12, y+h, x-w/4, y+h+10);
  line(x+w/12, y+h, x+w/4, y+h+10);
}