use bigint;

sub check {
	my ($bin, $three) = ('0b') x 2;
	my $s = $_;
	while ($s) {
		$three .= chop $s;
		$bin   .= chop $s;
	}
	return oct $three == 3 * oct $bin
}

$Regex_Pattern = qr/(?{ check() })/;