import java.io.*;
import java.net.*;

public class MiniServidor {

  public static void main (String args[]) {
    try{
      ServerSocket s = new ServerSocket(Integer.parseInt(args[0]));
      ArraySocket as= new ArraySocket();
      for (int i=0; i<3; i++) {
        Socket cs= s.accept();
        as.add(cs);    
        Client client = new Client(cs, as);
        client.start();
      }
      s.close();
    }  catch (Exception e) {  
      e.printStackTrace();
    }   
  }
}

class ArraySocket {
  Socket sockets[];
  int lastSocket;
  
  public ArraySocket (){
    sockets= new Socket[3];
    lastSocket=0;
  }
  public synchronized void add (Socket s){
    sockets[lastSocket++]=s;
  }
  public synchronized void send (String str, Socket excluir){
    System.out.println(excluir.getInetAddress().getHostAddress()+":"+
                       excluir.getPort()+"  "+str);
    try {
      for (int i=0; i< lastSocket; i++)
        if (sockets[i]!=excluir)
          new PrintWriter(sockets[i].getOutputStream(), true).println(str);
    } catch (Exception e) {  
      e.printStackTrace();
    }
  }
  public synchronized void remove(Socket s){  // esta implementación no se pedía
    int i;
    for (i=0; sockets[i]!=s && i<lastSocket; i++);
    if (i<lastSocket) sockets[i]=sockets[--lastSocket];    
  }
}

class Client extends Thread 
{
  ArraySocket as;
  Socket cs;

  public Client (Socket s, ArraySocket a){
    cs = s;
    as = a;
  }
        
  public void run () {
    boolean done=false;
    try{
      BufferedReader in = new BufferedReader
        (new InputStreamReader(cs.getInputStream()));
      while (!done) {  
        String line = in.readLine();
        if (line == null) done = true;
        else 
          as.send(line, cs);
      }
      as.remove(cs);
      cs.close();
    }  catch (Exception e) {  
      e.printStackTrace();
    }   
  }
}