You have:

use strict;

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which enabels strictures, see perldoc strict. You need to declare variables before using them, e.g. my $input;. Copying and pasting other peoples code without understanding it is a bad idea. Consider spending some time working your way through the following links:

Update: Also, don't ignore previous advice. See the responses to Re^2: How to get input text boxes populated.

In reply to Re^4: How to get input text boxes populated by marto
in thread How to get input text boxes populated by terrykhatri

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