public class DNSUtility
    {
        public static int Main (string [] args)
        {

          String strHostName = "";
          if (args.Length == 0)
          {
              // Getting Ip address of local machine...
              // First get the host name of local machine.
              strHostName = Dns.GetHostName ();
              Console.WriteLine ("Local Machine's Host Name: " + strHostName);
          }
          else
          {
              strHostName = args[0];
          }

          // Then using host name, get the IP address list..
          IPHostEntry ipEntry = Dns.GetHostByName (strHostName);
          IPAddress [] addr = ipEntry.AddressList;

          for (int i = 0; i < addr.Length; i++)
          {
              Console.WriteLine ("IP Address {0}: {1} ", i, addr[i].ToString());
          }
          return 0;
        }
     }

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