Adding Two Polynomials With A Linked List

I was supposed to write a PolyNode class for each node in the LinkedList, and a Polynomial class which is pretty much the list itself.Here is what I've coded so far:

PolyNode class:

public class PolyNode {
private int coefficient;
private int exponent;
private PolyNode next;

[code]....

The only trouble I'm having with this problem is finding a way to add these two polynomials together. My first attempt at it was to use nested while loops to traverse through both polynomial lists, like so:

public Polynomial addPolynomials(Polynomial p1, Polynomial p2) {
PolyNode current1 = p1.getFirstNode();
PolyNode current2 = p2.getFirstNode();
int coeff;
int expo;
Polynomial polySum = new Polynomial();

[code]....

Basically what this method does:

-Check to see if the exponents between two terms are the same
-If true, add their coefficients together
-Create a new node for the polySum with that coefficient sum and the particular exponent value
-At the end, return the polySum list which should be the sum of two polynomials

The problem with this method is it doesnt account for the values that are left behind because their exponents aren't equal to the exponents of the other list. So, the only terms that are getting added into the sum list are the ones that have the same exponent in both of the lists that are being added together.