- The user must put in some amount of money before an item can be selected.
- Only one item can be vended at a time.
- If the user selects an item that costs equal to or less than the amount of money that the user put in the vending machine, the program displays the change returned to the user.
- Vending machine items are stored in a file. The program keeps track of the following properties for each item: Item name Item cost Number of items in inventory