use strict;
use warnings;

my @one = qw( 1 2 3 5 6 8 10 );
my @two = qw( 2 4 6 8 10 );
print "One = @one\n";
print "Two = @two\n";
print "\n";

my %union;
@union{@one, @two} = ();
my @union = sort keys %union;
print "Union = @union\n";

my (%one, %two);
@one{@one} = ();
@two{@two} = ();

my %intersection = map {
    exists $one{$_} && exists $two{$_} 
    ? ($_ => undef) 
    : ()
} @one, @two;
my @intersection = sort keys %intersection;
print "Intersection = @intersection\n";

my %one_minus_two = map {
    exists $two{$_} 
    ? () 
    : ($_ => undef)
} @one;
my @one_minus_two = sort keys %one_minus_two;
print "One - Two = @one_minus_two\n";

my %symdiff = map {
    1 == ( exists($one{$_}) + exists($two{$_}) )
    ? ($_ => undef)
    : ()
} @one, @two;
my @symdiff = sort keys %symdiff;

print "Symdiff = @symdiff\n";