Add Two Numbers

public class Solution {

    static class ListNode {
        int val;

        ListNode next;

        ListNode(int x) {
            val = x;
        }
    }

    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {

        ListNode cur1 = l1;
        ListNode cur2 = l2;

        int sum = cur1.val + cur2.val;
        int hasCarry = 0;
        if (sum >= 10) {
            hasCarry = 1;
            sum -= 10;
        }

        ListNode result = new ListNode(sum);

        cur1 = cur1.next;
        cur2 = cur2.next;

        ListNode cur = result;

        while (cur1 != null && cur2 != null) {
            sum = cur1.val + cur2.val + hasCarry;
            if (sum >= 10) {
                hasCarry = 1;
                sum -= 10;
            } else {
                hasCarry = 0;
            }

            ListNode tmp = new ListNode(sum);
            cur.next = tmp;
            cur = tmp;

            cur1 = cur1.next;
            cur2 = cur2.next;
        }

        while (cur1 != null) {
            sum = cur1.val + hasCarry;
            if (sum >= 10) {
                hasCarry = 1;
                sum -= 10;
            } else {
                hasCarry = 0;
            }

            ListNode tmp = new ListNode(sum);
            cur.next = tmp;
            cur = tmp;
            cur1 = cur1.next;
        }

        while (cur2 != null) {
            sum = cur2.val + hasCarry;
            if (sum >= 10) {
                hasCarry = 1;
                sum -= 10;
            } else {
                hasCarry = 0;
            }

            ListNode tmp = new ListNode(sum);
            cur.next = tmp;
            cur = tmp;
            cur2 = cur2.next;
        }

        if (hasCarry > 0) {
            ListNode tmp = new ListNode(hasCarry);
            cur.next = tmp;
        }

        return result;

    }

    public static void main(String[] args) {
        //        Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
        //        Output: 7 -> 0 -> 8
        ListNode l1 = new ListNode(2);
        ListNode tmp = new ListNode(4);
        l1.next = tmp;
        tmp = new ListNode(3);
        l1.next.next = tmp;

        ListNode l2 = new ListNode(5);
        tmp = new ListNode(6);
        l2.next = tmp;
        tmp = new ListNode(4);
        l2.next.next = tmp;

        ListNode result = new Solution().addTwoNumbers(l1, l2);
        while (result != null) {
            System.out.print(result.val + " ");
            if (result != null)
                result = result.next;
        }

    }
}