import java.rmi.*;
import java.rmi.server.*;

public class EchoImpl extends UnicastRemoteObject implements Echo{
  
  public EchoImpl() throws RemoteException{
    super();
  }

  public String echo(String s) throws RemoteException {
    String res="";
    for(int i=0; i<s.length(); i++)
      res+=s.charAt(i)+"x";
    return res;
  }
}