BTW what would be the best perl functions to learn to help me with this sort of task in the future?

perlfunc has a section "Functions for SCALARs or strings". You should get a feeling for what each function does.

But of course they are only a toolbox, you have to learn how to use them effectively. That's not something that the perldocs teach you, it's what you learn from general programming books, books on algorithms, cookbooks, experience and from reading other people's code.