// CSE 143, Autumn 2013
// A LinkedIntList object stores a list of integers using a series of linked                                         
// node objects.  We will implement the same methods as ArrayIntList.  

public class LinkedIntList {
	private ListNode front;     // refers to first node in list (null if empty)

	// Constructs a new empty list.
    public LinkedIntList() {
        front = null;
    }

    // Adds the given value to the end of this list.
    public void add(int value) {
    	if (front == null) {
    		// empty list
    		front = new ListNode(value);
    	} else {
    		// non-empty list; walk to last node
    		ListNode current = front;
    		while(current.next != null) {
    			current = current.next;
    		}
    		// add new node at end of list
    		current.next = new ListNode(value);
    	}
    	
    }
    
    // Returns the element at the specified index from the list.
    // Precondition: 0 <= index < size
    public int get(int index) {
    	ListNode current = front;
    	for(int i = 0; i < index; i++) {
    		current = current.next;
    	}
    	return current.data;
    }
}