use Graph::Undirected;
my @colors = qw( black white red green blue cyan magenta yellow);
my @combos = (
               [qw(black cyan yellow)],
               [qw(red white blue)],
               [qw(white blue)],
               [qw(green red)],
               [qw(cyan magenta)],
               [qw(yellow magenta)],
               [qw(magenta cyan)],
               [qw(magenta black yellow)],
              );

my $g = Graph::Undirected->new(@colors);

for my $combo (@combos) {

# Special case of all @$combo <= 3, the following
#    can be replaced by:
#   $g->add_cycle( @$combo);

    for my $pick (0..$#$combo-1) {
         $g->add_edge( $combo->[$pick], $combo->[$_]) for $pick+1..$#$combo;
    }
}

my @components = $g->strongly_connected_components;
print "@$_", $/ for @components;