You've changed your OP without indicating what's been changed. Please don't do this. "How do I change/delete my post?" explains how to update a node (and why you should do it this way).

You've added code to your OP which differs from the code you posted in reply to my original response. This is not helpful.

Strings in double-quotes are interpolated. When perl sees "... @whatever ...". it assumes @whatever is an array. You can use single-quotes to stop interpolation or escape the '@' character (as you did in "SET \@num := 0, \@id := -1;").