Sorry! How strange of Perl to be asymmetric! Why is "--" not as magical as "++"? This will work instead... 
$char_up =~ tr/A-Z0-9/B-ZZ1-99/;
$char_down =~ tr/A-Z0-9/AA-Y00-8/;

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In reply to Re^3: searching for strings by shoness
in thread searching for strings by steph_bow

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