#!/usr/bin/perl -w
use strict;
use Algorithm::Loops qw(NestedLoops);


my @symbol = (
   [ 'a', 'b', 'c' ],
   [ 'a', 'b', 'c'  ],
   [ 'a', 'b', 'c'  ],
   [ 'c', 'd', 'e'  ],
);

my $iter = NestedLoops(\@symbol);
my %seen;

while (my @list = $iter->()) {
    my $listString = join ('',sort @list);
    $seen{$listString}++
}

my @sortedUniq = sort (keys %seen);

foreach my $sortedUniq (@sortedUniq) {
    print $sortedUniq,"\n";
}