Did you say "golf"? :-)

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sub b262b10{ my$n;$n++for"a"..lc$_[0];$n }
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27

Update: Make that 26. I can save a stroke by reusing @_. :-)

sub b262b10{ $_[1]++for"a"..lc$_[0];pop }
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-sauoq
"My two cents aren't worth a dime.";