leetcode--Add Two Numbers

You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
        ListNode head = new ListNode(0);
		ListNode currentNode = head;
		int carry = 0;
		while(l1 != null && l2 != null){
			int sum = l1.val + l2.val + carry;
			carry = sum / 10;
			currentNode.next = new ListNode(sum % 10);
			currentNode = currentNode.next;
			l1 = l1.next;
			l2 = l2.next;
		}
		
		ListNode remaining = (l1 == null) ? l2 : l1;
		while(remaining != null){
			int sum = remaining.val + carry;
			carry = sum / 10;
			currentNode.next = new ListNode(sum % 10);
			currentNode = currentNode.next;
			remaining = remaining.next;
		}
		if(carry != 0)
			currentNode.next = new ListNode(1);
		
		head = head.next;
		return head;    
    }
}