/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* addTwoNumbers(ListNode* l1, ListNode* l2)
{
ListNode* head = new ListNode(0);
ListNode *p = head;
int sum = 0;
bool carry = false;
while (l1 || l2)
{
sum = 0;
if (l1 != NULL)
{
sum += l1->val;
l1 = l1->next;
}
if (l2 != NULL)
{
sum += l2->val;
l2 = l2->next;
}
if (carry)
{
sum++;
}
p->next = new ListNode(sum % 10);
p = p->next;
carry = sum >= 10 ? true : false;
}
if (carry)
{
p->next = new ListNode(1);
}
return head->next;
}
};
