刷题笔记（leetcode02-两数相加）

普通的循环解法，C代码：

 1 /**
 2  * Definition for singly-linked list.
 3  * struct ListNode {
 4  *     int val;
 5  *     struct ListNode *next;
 6  * };
 7  */
 8 
 9 
10 struct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2){
11     int total = 0, next1 = 0;
12 
13     struct ListNode *result = (struct ListNode *)malloc(sizeof(struct ListNode));
14     struct ListNode *cur = result;
15     cur->next = NULL;
16 
17     while(l1 && l2){
18         total = l1->val + l2->val + next1;
19         cur->next = (struct ListNode *)malloc(sizeof(struct ListNode));
20         cur->next->val = total % 10;
21         cur->next->next = NULL;
22         next1 = total / 10;
23         l1 = l1->next;
24         l2 = l2->next;
25         cur = cur->next;
26     }
27 
28     while(l1){
29         total = l1->val + next1;
30         cur->next = (struct ListNode *)malloc(sizeof(struct ListNode));
31         cur->next->val = total % 10;
32         cur->next->next = NULL;
33         next1 = total / 10;
34         l1 = l1->next;
35         cur = cur->next;
36     }
37 
38     while(l2){
39         total = l2->val + next1;
40         cur->next = (struct ListNode *)malloc(sizeof(struct ListNode));
41         cur->next->val = total % 10;
42         next1 = total / 10;
43         cur->next->next = NULL;
44         l2 = l1->next;
45         cur = cur->next;
46     }
47 
48     if(next1 != 0){
49         cur->next = (struct ListNode *)malloc(sizeof(struct ListNode));
50         cur->next->val = next1;
51         cur->next->next = NULL;
52     }
53 
54     return result->next;
55 
56 }