sub improved {
	my $c = ord(1);
	my $temp = join $c, @array2;
	@array1 = grep { -1==index($temp, $c . $_ . $c ) } @array1;
}

##</code><code>##

sub perlfaq {
  my %hash;
  @hash{@array2} = ((undef) x @array2);
  @array1 = grep { not exists $hash{$_} } @array1;
}