class Kirp implements Paiknev{
   private double _x, _y;
   public Kirp(){
      _x=Math.random(); _y=Math.random();
   }
   public double x(){return _x;}
   public double y(){return _y;}
   public void hyppa(){
      _x=_x+Math.random()-0.5;
      _y=_y+Math.random()-0.5;
   }
}