I cannot resist to provide my take on it as well... 

use strict; use warnings;
my $_ = "AAAGCCCCTTTAAACCCCxxxxxx";
my %h;
$h{$_}++ for /./g; 
print "ACGT only: ", join " ", @h{qw(A C G T)}, "\n";
print "All chars: ", join " ", @h{sort keys%h}, "\n";

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In reply to Re: Entering the land of Perl by hdb
in thread Entering the land of Perl by manbroski

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