Is there any reason why you couldn't just use this? 
my $num = $ARGV[0];

$num .= 'st' if (substr($num, -1) == 1);
$num .= 'nd' if (substr($num, -1) == 2);
$num .= 'rd' if (substr($num, -1) == 3);
$num .= 'th' if (substr($num, -1)  > 3);

print "$num\n";

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In reply to Re: adding st,nd,rd and th to numbers by zshzn
in thread adding st,nd,rd and th to numbers by anniyan

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