use warnings;
use strict;
use List::Compare;
use Data::Dumper;

my @file1 = qw{1 2 3 4  };
my @file2 = qw{  2 3 4 5};

my $lc = List::Compare->new( {
    lists => [\@file1, \@file2],
} );

my @intersection = $lc->get_intersection();
my @file1_only = $lc->get_Lonly();
my @file2_only = $lc->get_Ronly();

print Dumper \@intersection, \@file1_only, \@file2_only;