Welcome to PerlMonks!

Please read How do I compose an effective node title?, How do I post a question effectively? and Markup in the Monastery for more effective posting.

That out of the way though, you’re best off consulting perldoc -f split about the split function (and play around with it, it’s fun), perldoc perlsyn about Foreach Loops and perldoc perlop about mathematical (and other) operators.

Have fun!