I need help in my program. I'm asked to sort all the names in the phone book alphabetically. How can I do it?

1. Open a phonebook.
2. Starting from the top left corner of the first page, type in all the names in order of appearance.
3. Repeat for all 800+ pages.
4. Print the names out in the same order. Phonebooks are already sorted alphabetically.
5. Read the guidelines.

sorry i didn't mean that i need to sort the names which they r not sorted in a file
(names r strings) thnx alot