public void generatePowerups(){
		Random random = new Random();
		int ammoProbability = (1 + ammo.size())*1000;
		int healthProbability = (1 + health.size())*1000;
		if(random.nextInt(ammoProbability)==1){
			addAmmo();
		}
		if(random.nextInt(healthProbability)==1){
			addHealth();
		}
	}