Hey peoples!

Sorry, I'm back again. I realize that there was a recent thread about password encryption, so I do apologise for creating another. But I was reading that thread, and I read about a sort of "table of characters" method of encryption that I wanted to try. I understand the concept, but I don't know how it can be implemented. I started my function (well bool to be exact,) to simply take a string, go through it character by character, and based on the table, change it into it's designated symbol/number/letter. In my case, number. Then I intend to convert it to an int, and preform some mathematical calculations on it.

How can this be achieved?
Thanks for any future replies or any useful information you can provide.