The Eversoft Eraser Company has the list of its customers' names (not necessarily in alphabetical order) and telephone numbers in the file named "customer" with records of following given form:

Last name, first name, phone number

a) Enable the user in order to input a last name; then find the file and show all the names and phone numbers corresponding to that last name.

b) Load file into the parallel arrays and show the list of customers' names and phone numbers in the alphabetical order.