#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <netdb.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

int main (argc,argv) 
int argc;
char **argv;
{ 
  int i,j;
  int rc=0;
  char s[1024];
  struct in_addr addr;

  typedef struct hostent Host;
  Host *host;

  for (i=1;i<argc;i++)
  { 
    for (j=0;j<256;j++) /* whole class C */
    {
      sprintf (s,"%s.%d",*(argv+i),j);
      if (!(inet_aton (s,&addr) == 1)) { rc=1; break;}
      host=gethostbyaddr((char *)&addr,sizeof(struct in_addr),AF_INET); 
      if ( host == NULL ) printf ("%s\n",s);
    }
  }
return rc;
}