Can't you use a hash? 
my $string = "aabbbcc";
my @array = split('',$string);
my %hash = ();
foreach (@array) {
  print "dup found!\n" if (exists($hash{$_}));
  $hash{$_}++;
}

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In reply to Re: Recognizing duplicates by perlfan
in thread Recognizing duplicates by b4swine

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