To get rid of the warnings, you can write 

if (defined $data{$key} && $data{$key} eq $input) {
   ...
}

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Also, please do read, understand and apply Writeup Formatting Tips.

Perl 6 - the future is here, just unevenly distributed

In reply to Re^3: Extracting single element from array to be printed in a one liner hash by moritz
in thread Extracting single element from array to be printed in a one liner hash by wildguess123

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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