Since you can't run the script on the command-line (not sure why), and you most likely will get other syntax errors in the future, you might like to add near the top of your script (after the #! line): 
use CGI::Carp qw(fatalsToBrowser);

[download]
This will send error messages to the browser so you can see them. You probably don't want that in production.
You error is that you need $num = ""; or just my $num;

In reply to Re: I'm getting a 500 Internal Server Error - how can I make this work? by cdarke
in thread I'm getting a 500 Internal Server Error - how can I make this work? by linex

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