（a）机器能自动识别硬币金额，最大为一元，最小为一角。购票者可选择的邮票面值有一元和五角两种，每次只能售出一枚邮票；

（b）购票时先选择邮票面值后投币，当投入的硬币总金额达到或超过邮票面值时，机器应发出指示并拒收继续投入的硬币；

（c）购票者投币后，按动确认键，机器将发出邮票和找零硬币，若所投金额不足，则发出欠资指示。在欠资情况下，购票者可以继续投币购票，也可按取消键，则机器将退出所投入的全部金额；

-there is a slot machine, you can only put one coin, but you can put more coins continuously. The machine can identify the amount of coins of 1 yuan, 5 angle and a corner. Customers may choose 1 per drink price, 1 per 5 angle, 2 yuan of three. You can only sell a bottle of drink. 2, the first choice when buying drinks again beverage prices coin, when the total amount of coins into the drink prices reached or exceeded, the machine refused to give directions to input signals and coins. After the customer coin, press the OK button, the machine will issue a change for drinks and coins, and if the investment amount, then the issue of postage due signaling. In less funding, customers can continue to buy coin, but also can cancel button, the machine will be out of the full amount invested.