import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)

/**
 * Write a description of class maus here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class maus extends Actor
{
         int Z = 0;  
    
    public void act() 
    {
      this.move(3);
      if(Greenfoot.isKeyDown("left"))turn(-5);
      if(Greenfoot.isKeyDown("right"))turn(5);
      prüfeRänder();      
}

public void prüfeRänder() {
    if(this.isAtEdge()) turn(180);
}
}