this accepts multiple arguments,and uses a hash to build a unique directory list.

#!/usr/bin/perl
require 5.006;
use strict;
use warnings;
$|++;

use File::Find ();

my %dirs;
while( $_ = shift @ARGV )
{
  next unless -d $_;
  File::Find::find 
    sub{ -d $File::Find::name and $dirs{$File::Find::name} = undef }, 
    $_;
}
print $_,$/ for sort keys %dirs;
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~Particle *accelerates*