Your s/// for converting characters to lowercase is far too much work, and the use of $& is poisonous. I'd use the lc() function.

And you're using substr() where chop() would do, and probably where you could just use split(). 

while (<STDIN>) {
  $count{$_}++ for split //, lc;
}

[download]
Is how I would optimize your input loop.

japhy -- Perl and Regex Hacker

In reply to Re: Frequency Analyzer by japhy
in thread Frequency Analyzer by Big Willy

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