#!/opt/default/bin/perl

use Socket;

while (<>) {
	chomp;
	if (/\d+\.\d+\.\d+\.\d+/) {
		my $name = gethostbyaddr(inet_aton($_), AF_INET);
		print "\t$name\n";
		next;
	}
	my $adr = gethostbyname($_);
	my $dotted = "?";
	$dotted = inet_ntoa($adr) if $adr;
	print "\t$dotted\n";
}