#include <iostream>
#include "IntegerList.h"

IntegerList::IntegerList()			// constructor
	: head(NULL), n(0) { }

int& IntegerList::front() 		// return front element
{
	if (n==0) throw length_error("empty list");
	return head->getElement();
}

IntegerList::~IntegerList()			// destructor
{
	while (n > 0) removeFront();
}

void IntegerList::addFront(int e) {	// add to front of list
	IntListNode* v = new IntListNode(e, head);		// create new node
	head = v;				// v is now the head
	n++;
}

void IntegerList::removeFront() {		// remove front item
	if (n == 0) throw length_error("empty list");
	IntListNode* old = head;		// save current head
	head = old->getNext();			// skip over old head
	delete old;				// delete the old head
	n--;
}

void IntegerList::print() {		// print all elements
	IntListNode* current = head;
	while (current != NULL) {
		std::cout << current->getElement() << endl;
		current = current->getNext();
	}
}

int IntegerList::size() const {				// list size
	return n;
}