I ) (20 pts. ) - Many online and offline services are associated with a user identity and credential. In this assignment, you will create a rudimentary (and highly insecure) database for the storage of only the user generated identities. This program will have the following behaviors: (line break, 11 pt)

A) (4 / 30 pts. ) - Prior to prompting for a new username, the existing list of usernames should be read and loaded to an array. 1 ) Read the list from "users.txt", a prompt is not necessary. 2 ) The existing list of usernames should be written to the console. (line break, 11 pt)

B) (18 / 30 pts. ) - Upon prompting, the following checks must be made against an attempt to create a new username. 1 ) Duplicate usernames should be disallowed, and the usernames are case sensitive. 2 ) Usernames must be between 3 and 6 characters in length. 3 ) Username cant contain any space. 4) Usernames must start with a letter like [a-z A-Z] 5) Usernames must have at least one number like [0-9] 6) If the rules from 1-5 are violated, an appropriate error message informing the user should be displayed. i ) The error message should display *all* the reasons why the username is not correct. ii ) Do not display merely the first problem the program identifies (unless, of course, the first problem is the only problem). (line break, 11 pt)

C) (4 / 30 pts. ) - When a valid username is provided, this username should be written to an array and printed back to console. (line break, 11 pt)

D) (4 / 30 pts. ) - Finally, the "users.txt" database should be updated such that the new username appears should the program be run again.