Untested: 
use List::Util 'reduce';
use 5.010;
my %hash;
$hash{$_}++ for split //, $my_string;
say "Most frequent: ", reduce {$hash{$a} > $hash{$b} ? $a : $b} keys %
+hash;

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In reply to Re: Quick way to find the letter with the most occurences in a string by JavaFan
in thread Quick way to find the letter with the most occurences in a string by Anonymous Monk

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