import java.util.Scanner;
import java.util.ArrayList;
import java.util.*;

/**
 * Created by leon on 1/23/18.
 */
public class PhoneBook {
    private String name;
    private String phoneNumber;
    TreeMap<String, String>phonebook = new TreeMap<>(); 

    public PhoneBook()
    {        
    }
    
    public PhoneBook(String name, String phoneNumber) {
    this.name = name; this.phoneNumber = phoneNumber; 
    }

    public PhoneBook (TreeMap<String, String>phonebook) {
        this.phonebook = phonebook;
    }

    public void add(String name, String phoneNumber) {
        phonebook.put(name, phoneNumber); 
    }

    public void remove(String name) {
        phonebook.remove(name); 
    }
    
    public void removeRecord() {
     phonebook.clear();   
    }

    public Collection<String> lookup (String name) {
        return phonebook.values();   
    }

    public Collection<String> reverseLookup(String phoneNumber) {
        return phonebook.keySet();
    }

    public TreeMap<String, String> display() {
        return phonebook; 
    }

    public void entries () {

    } 
}