I'm trying to create a program that reads in 3 digit prefixes from a text file and compares those digits to a series of other prefixes belonging to a certain groups.
When it finds which group the given prefix belongs to, it stores and later displays how many prefixes belonged to each group.

Example of the groups:
Portland - Nextel Communications: 206,519,572,793,849,969
Sunnyside - GTE: 638,673

Now if I wanted to just code in the groups and their corresponding prefixes, I wouldn't be having any problems. However, since there are many groups, and the list will continue to grow, I want to add-in a feature allowing me to add groups in as they are needed. (i.e. I want to have a file which I can edit that stores the name of each group and their prefixes, that my program will read at run time.) This is where my problem comes in. I don't know how I can "link" the group names, and their prefixes together. I tried using multidimensional arrays, but that became even more of a headache(quite possibly due to my inexperience with them).

I hope I was clear enough about my situation, if not please let me know. Any help with this problem would be GREATLY appreciated as I've spent many hours trying to figure out a way to do it.

-Peter