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Exercise 7.5
A subclass of LotteryAccount

On the slide, to which this exercise belongs, we have emphasized inheritance of methods and properties in the bank account class hierarchy. From the web-version of the material there is direct access to the necessary pieces of program.

The LotteryAccount uses an instance of a Lottery object for adding interests. Under some lucky circumstances, the owner of a LotteryAccount will get a substantial amount of interests. In most cases, however, no interests will be added.

There exists a single file which contains the classes BankAccount, CheckAccount, SavingsAccount, Lottery, together with a sample client class.

Program a specialization of the LotteryAccount, called LotteyPlusAccount, with the following redefinitions of Deposit and Withdraw.

Notice that the Deposit and Withdraw methods in LotteryPlusAccount should combine with the method in LotteryAccount (method combination). Thus, use the Deposit and Withdraw methods from LotteryAccount as much as possible when you program the LotteryPlusAccount.

Test-drive the class LotteryPlusAccount from a sample client class.