use warnings;
use strict;

use List::Compare;

my @S1 = ( 'G1', 'G3', 'G5' );

my @S2 = ( 'G1', 'G3', 'G5', 'G7', 'G12' );

my @S3 = ( 'G1', 'G5' );

my @A = ('\@S1', '\@S2', '\@S3');

my $var = join ',' , @A;

my $lc = List::Compare->new('--unsorted', "$var");

my @intersection = $lc->get_intersection;

print "intesection is @intersection\n";