Add Two Numbers (Rewrite)

//class ListNode { // public: // int value; // ListNode* next; // ListNode(int v) : value(v), next(NULL) {} //}; class Solution { public: ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) { // write your solution here ListNode * p1 = l1; ListNode * p2 = l2; ListNode * dummy = new ListNode(0); ListNode * p3 = dummy; int curr = 0; int carry = 0; while(p1 != nullptr || p2 != nullptr){ if (p1 != nullptr){ curr += p1->value; p1 = p1->next; } if (p2 != nullptr){ curr += p2->value; p2 = p2->next; } curr += carry; carry = 0; if (curr > 9){ curr -= 10; carry = 1; } p3->next = new ListNode(curr); curr = 0; p3 = p3->next; } if (carry == 1){ p3->next = new ListNode(1); } return dummy->next; } };