import java.io.*; 
 import java.net.*; 
 import java.nio.*; 
 import java.nio.channels.*; 
 import java.nio.charset.*; 
 import java.util.*; 
 import java.util.regex.*; 
  
  
 public class Ping { 
  
   // The default daytime port 
   static int DAYTIME_PORT = 13; 
  
   // The port we'll actually use 
   static int port = DAYTIME_PORT; 
  
  
   // Representation of a ping target 
   //  
   static class Target { 
  
 	InetSocketAddress address; 
 	SocketChannel channel; 
 	Exception failure; 
 	long connectStart; 
 	long connectFinish = 0; 
 	boolean shown = false; 
  
 	Target(String host) { 
 	  try { 
 		address = new InetSocketAddress(InetAddress.getByName(host), 
 						port); 
 	  } catch (IOException x) { 
 		failure = x; 
 	  } 
 	} 
  
 	void show() { 
 	  String result; 
 	  if (connectFinish != 0) 
 		result = Long.toString(connectFinish - connectStart) + "ms"; 
 	  else if (failure != null) 
 		result = failure.toString(); 
 	  else 
 		result = "Timed out"; 
 	  System.out.println(address + " : " + result); 
 	  shown = true; 
 	} 
  
   } 
  
  
   // Thread for printing targets as they're heard from 
   // 
   static class Printer 
 	extends Thread 
   { 
 	LinkedList pending = new LinkedList(); 
  
 	Printer() { 
 	  setName("Printer"); 
 	  setDaemon(true); 
 	} 
  
 	void add(Target t) { 
 	  synchronized (pending) { 
 		pending.add(t); 
 		pending.notify(); 
 	  } 
 	} 
  
 	public void run() { 
 	  try { 
 		for (;;) { 
 		  Target t = null; 
 		  synchronized (pending) { 
 			while (pending.size() == 0) 
 			  pending.wait(); 
 			t = (Target)pending.removeFirst(); 
 		  } 
 		  t.show(); 
 		} 
 	  } catch (InterruptedException x) { 
 		return; 
 	  } 
 	} 
  
   } 
  
  
   // Thread for connecting to all targets in parallel via a single selector 
   //  
   static class Connector 
 	extends Thread 
   { 
 	Selector sel; 
 	Printer printer; 
  
 	// List of pending targets.  We use this list because if we try to 
 	// register a channel with the selector while the connector thread is 
 	// blocked in the selector then we will block. 
 	// 
 	LinkedList pending = new LinkedList(); 
  
 	Connector(Printer pr) throws IOException { 
 	  printer = pr; 
 	  sel = Selector.open(); 
 	  setName("Connector"); 
 	} 
  
 	// Initiate a connection sequence to the given target and add the 
 	// target to the pending-target list 
 	// 
 	void add(Target t) { 
 	  SocketChannel sc = null; 
 	  try { 
  
 		// Open the channel, set it to non-blocking, initiate connect 
 		sc = SocketChannel.open(); 
 		sc.configureBlocking(false); 
  
 		boolean connected = sc.connect(t.address); 
  
 		// Record the time we started 
 		t.channel = sc; 
 		t.connectStart = System.currentTimeMillis(); 
  
 		if (connected) { 
 		  t.connectFinish = t.connectStart; 
 		  sc.close(); 
 		  printer.add(t); 
 		} else {