/**
 * Write a description of class HashFun420 here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */

import java.util.*;

public class HashFun
{
    public static void main(String[] args) {
        Map<String, String> phonebook = new Hashtable<String,String>();
        
        //System.out.println("Empty:" + phonebook.isEmpty());
        
        phonebook.put("John", "617-123-4567");

        //System.out.println("Empty:" + phonebook.isEmpty());
        
        //System.out.println("John's phone number:" + phonebook.get("John"));
        
        phonebook.put("Natalia", "617-123-4117");
        phonebook.put("Fred", "617-123-1111");
        phonebook.put("Li", "617-123-6785");
        
        Set<String> keys = phonebook.keySet();
        Iterator<String> it = keys.iterator();
		// could alternatively do this in one line:
		// Iterator<String> it = phonebook.keySet().iterator();        

        String akey;
        while(it.hasNext()) {
            akey = it.next();
            System.out.println(akey + ":" + phonebook.get(akey));            
            
        }
        
    }

}