Not sure if you want unique directory names or directory paths, but either way just take a lesson from perldoc perlfaq4 - How can I get the unique keys from two hashes.

#!/usr/bin/perl

use Cwd;
use File::Find;

use warnings;
use strict;

my $cwd = getcwd();

my %seen;

find(sub {
    print "$_\n" if -d $File::Find::name && !$seen{$_}++;
}, $cwd);
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