You are given two non-empty linked lists representing two non-negative integers. 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.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
Example:
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4) Output: 7 -> 0 -> 8 Explanation: 342 + 465 = 807.
/** * 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) { if(!l1 && !l2) return nullptr; if(!l1) { return addTwoNumbers(l2, l1); } int val = l1->val + (l2? l2->val: 0); if(val/10) { l1->next = l1->next? l1->next: new ListNode(0); l1->next->val += 1; } l1->val = val%10; l1->next = addTwoNumbers(l1->next, l2?l2->next:nullptr); return l1; } };
原文：https://www.cnblogs.com/BlackYao/p/12095911.html