use strict;
use warnings;

my @letters = qw(A B C D E F);
my $string = "AFTYUBEWTWECRTUTYIYTDDDDRYJURTHJTREEEEEFGSDFF";
my %chCount;

++$chCount{$_} for split '', $string;
print "$_ = $chCount{$_}\n" for @letters;

##</code><code>##

A = 1
B = 1
C = 1
D = 5
E = 7
F = 4