public class Driver {
	public static void main(String[] args) {
		ShoppingBag sb = new ShoppingBag();

		sb.addItem("sweater", 40);
		sb.addItem("socks", 10);

		System.out.println("the bag: " + sb.toString());
		System.out.println("the bag contains a sweater: " 
						   + sb.containsItem("sweater"));
		System.out.println("average item cost: "
						   + sb.getAverageItemCost());		
	}
}