use strict;
use warnings;
my @AOA1 = ( [2342, 1], [2444, 2], [3333, 3] );
my @AOA2 = ( [2444, 2], [3333, 3], [1234, 1] );
my @diff;
{
    my %crossref;
	$crossref{ join "|", @{$_} }++ foreach ( @AOA1, @AOA2 );
	foreach my $key ( keys %crossref ) {
		push @diff, [ split( /\|/, $key ) ] if $crossref{$key} < 2;
	}
}
print "@{$_}\n" for @diff;