Assuming that the script works from your shell command-line, the problem is likely to be the different environment the cron job runs in. For example, maybe you have PERL5LIB in your environment, and cron probably won't.

The easiest way to troubleshoot this specific problem would be to see where List/Compare.pm is located, then make sure that directory is at the top of your script with a use lib statement.

Another idea is to run a shell with no environment, with something like env - bash. Getting your script to work in that environment should ensure it works with cron as well.