public class PhoneBook
{
    Node<Phone> first;
    Node<Phone> last;

    public PhoneBook() // no costumer
    {
        first = null;
        last  = null ;
    }

    public PhoneBook(Phone a) // Bank with only one consumer
    {
        Node <Phone> n = new Node<Phone> (a);
        first  = n;
        last = first;
    }

    public void addContact(String name, String num)
    {
        Phone a = new Phone (name, num);
        Node<Phone> abc = new Node <Phone> (a);
        Node<Phone> p = first;

        //if there is something in list add to the last
        if (p != null)
        {
            Node <Phone> last = first;
            while (last.getNext() != null)
            {
                last = last.getNext();
            }
            last.setNext(abc);
        }
        //if there isnt something in list add to the beginning
        else
        {
            abc.setNext(first);
            first = abc;
        }
    }

    public void removeContact(Phone a)
    {
        Node<Phone> p = first;
	Node<Phone> save = first;
        int i = 0;

        while (!(p.getValue().getName().equals(a.getName())))
        {
            p = p.getNext();
        }

        p = first;

        if(i==0)
        {
            first = p.getNext();

            while(p != null)
            {
		p = p.getNext();
            }
        }
        else
        {
            while(save.getNext() != p)
            {
                save = save.getNext();
            }
            p = null;
            save.setNext(p);
        }
    }

    public  String [] getAllContactsNames()
    {
        Node<Phone> p = first;
        int i = 0;

        while (p != null)
        {
            i++;
            p = p.getNext();
        }

        String [] s = new String [i];
        p = first;

        for(int j = 0; j < i; j++)
        {
            s[j] = p.getValue().getName();
        }

        return s;
    }

    void setPhone (String name, String phone)
    {
        Node <Phone> p = first;

        while (!(p.getValue().getName().equals(name)))
        {
            p = p.getNext();
        }
        p.getValue().setNum(phone);
    }

    public String toString()
    {
        String s = "";
        Node<Phone> p = first;

        while (p!=null)
        {
            s += "\n" + p.getValue().toString();
            p = p.getNext();
        }

        return s;
    }
}