First of all see How (not) to ask a question.

You need something like: 

my %seen;
for (@input) {
   $seen{$_}++ && warn "$_ already entered\n";
}

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-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.

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In reply to Re: huge problem! by Joost
in thread Inserting sequences without duplicates by husoft

Title:
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