A local used record store wishes to automate their inventory tracking system. Three types of items are to be tracked: Rock CDs, Classical CDs and DVDs. Purchases and trades of used items by customers are also to be tracked.
- Purchase: removes an item from the inventory
- Trade-in: adds an item to the inventory
- Display: outputs the entire inventory of the store, including the number of each item in inventory
- History: outputs all of the transactions for a customer including the item (in chronological order)
- HistoryAll: outputs the history for every customer, with the customers in alphabetical order.