public class duplicate

{

public static void main(String[] args)throws IOException

  {

  System.out.println("Enter words separated by spaces ('.' to quit):");

  Set<String> s = new HashSet<String>();

  Scanner input = new Scanner(System.in);

  while (true)

  {

  String token = input.next();

  if (".".equals(token))

  break;

  if (!s.add(token))

  System.out.println("Duplicate detected: " + token);

  }

  System.out.println(s.size() + " distinct words:\n" + s);

} }

my program detects and prints duplicate words but i need to print the number of duplicate words also. pls help me do it.