public void listen() {
		while (true) {
			String userInput = keypad.nextLine();
			int[] money;
			if (userInput.equals("Penny")) {
				money = cashier.addMoney(1);
				int[] penny = {0, 1};
				System.out.println(cashier.returnChange(penny));
				System.out.println(Cashier.showCash(cashier.currentValue()));
			} else if (userInput.equals("Nickel")) {
				money = cashier.addMoney(5);
				System.out.println(Cashier.showCash(money));
			} else if (userInput.equals("Dime")) {
				money = cashier.addMoney(10);
				System.out.println(Cashier.showCash(money));
			} else if (userInput.equals("Quarter")) {
				money = cashier.addMoney(25);
				System.out.println(Cashier.showCash(money));
			} else if (userInput.length() == 2) {
				boolean purchased = im.attemptPurchase(userInput, cashier.currentValue());
				if (purchased) {
					int priceInPennies = Cashier.toPennies(im.find(userInput).getProduct().getPrice());
					cashier.purchase(priceInPennies);
					System.out.println("Purchased!");
					System.out.println(cashier.returnChange(cashier.currentValue()));
					System.out.println(Cashier.showCash(cashier.currentValue()));
				} else {
					System.out.println("Not purchased! Maybe not enough money, or bad code, or out of stock!");
					System.out.println(Cashier.showCash(cashier.currentValue()));
				}
			} else if (userInput.equals("Return")) {
				System.out.println(cashier.returnChange(cashier.currentValue()));
			} else {
				System.out.println("Input not recognized as money or snack selection. Ignoring.");
			}
		}
	}