A local bank has asked the software development company you work for to develop an expense tracking system for their customers. Tracking expenses is often the first step in getting people’s finances in order. If you do not know how much you have spent each month, you cannot tell when you have overspent. By understanding what you spend money on and how much you spend, you can see exactly where your cash is going. The company has handed the responsibility for its development on to you.

You should write a program that implements an expense tracking system. Your program should allow the bank customers to create an account with a username and password. The usernames can only contain letters and numbers. The password must be at least EIGHT (8) characters long, and contain at least ONE (1) lowercase and ONE (1) uppercase letter.