Add Two Numbers(单链表处理)

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.

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
C++

/** * 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* sum=l1;        int flag=0;        for(;;)        {            int val=(l1->val+l2->val+flag)%10;            flag=(l1->val+l2->val+flag)/10;            l1->val=val;            //结束循环条件是其中一个链表到达末尾了            if(l1->next == NULL || l2->next == NULL)            {                break;            }            l1=l1->next;            l2=l2->next;        }        //如果l2.Next不为空,就拼接到l1后面,否则不用做什么        if(l2->next!=NULL)        {            l1->next=l2->next;        }        //处理进位问题导致的合并之后链表的变更        for(;;)        {            //结束循环条件就是没有进位了,或到达了链表末尾            if(flag==0 || l1->next==NULL)            {                break;            }            l1=l1->next;            int val=(l1->val+flag)%10;            flag=(l1->val+flag)/10;            l1->val=val;        }        //处理最后一个进位        if(flag>0)        {            l1->next=new ListNode(flag);        }        return sum;    }};

go:

/** * Definition for singly-linked list. * type ListNode struct { *     Val int *     Next *ListNode * } */func addTwoNumbers(l1 *ListNode, l2 *ListNode) *ListNode {    sum:=l1    flag:=0    for{        Val:=(l1.Val+l2.Val+flag)%10        flag=(l1.Val+l2.Val+flag)/10        l1.Val=Val        if  l1.Next== nil || l2.Next ==nil{            break        }         l1=l1.Next         l2=l2.Next    }    if l2.Next !=nil {        l1.Next=l2.Next    }    for flag >0 && l1 !=nil && l1.Next != nil{        l1=l1.Next        Val:=(l1.Val+flag)%10        flag=(l1.Val+flag)/10        l1.Val=Val    }    if flag>0{        l1.Next=&ListNode{}        l1=l1.Next        l1.Val=flag        l1.Next=nil    }    return sum}