import java.net.*;


public class ReverseTest {

  public static void main (String args[]) {
  
    try {
      InetAddress ia = InetAddress.getByName("152.2.22.3");
      System.out.println(ia.getHostName());
    }
    catch (Exception e) {
      System.err.println(e);
    }
   
  }

}