class program {

void voltea(){
	iterate(2){
		turnleft();
	}
}

void giraDerecha(){
	voltea();
	turnleft();
}

void ponPalo(){
	if (notNextToABeeper()){
		putbeeper();
		putbeeper();
	}
}

void esVaca(){
	pickbeeper();
	if (nextToABeeper()){
		putbeeper();
	}
}

void buscarVaca(){
	while(iszero(0)){
		if (nextToABeeper()){
			esVaca();
			if (notNextToABeeper()){
				putbeeper();
				return();
			}
		}
		while(frontIsClear()){
			move();
			if (nextToABeeper()){
				esVaca();
				if (notNextToABeeper()){
					putbeeper();
					return();
				}
			}
		}
		voltea();
		while(frontIsClear()){
			move();
		}
		turnleft();
		if (frontIsClear()){
			move();
			turnleft();
		}else{
			return();
		}
	}
}

void avanzaCasilla(){
	if (frontIsClear()){
		move();
	}else{
		voltea();
		while(frontIsClear()){
			move();
		}
		turnleft();
		if (frontIsClear()){
			move();
			turnleft();
		}else{
			return();
		}
	}
}

void ponBarda(){
	if (frontIsClear()){
		move();
		ponPalo();
		turnleft();
		if (frontIsClear()){
			move();
			ponPalo();
			voltea();
			move();
		 }else{
			 voltea();
		 }
		 if (frontIsClear()){
			move();
			ponPalo();
			voltea();
			move();
		 }else{
			 voltea();
		 }
		 turnleft();
		 move();
		 turnleft();
	}else{
		giraDerecha();
	}
}

void ponCerca(){
	iterate(4){
		ponBarda();
	}
}

program() {
	while(iszero(0)){
		buscarVaca();
		if (facingEast()){
			turnoff();
		}else{
			ponCerca();
			avanzaCasilla();
		}
	}
}

}