leetcode_c++：链表：add two numbers（002）

*

#include <iostream>
#include <vector>
#include <map>
#include <string>
#include <algorithm>
#include <cmath>

using namespace std;

struct ListNode{
    int val;
    ListNode *next;
    ListNode(int x):val(x),next(NULL){}
};


//尾插法

ListNode *addValAndCreateNewNode(ListNode *cur,int val){
    cur->val=val;
    cur->next=new ListNode(0);
    return cur->next;
}

class Solution{
public:
    ListNode *addTwoNumbers(ListNode *l1,ListNode *l2){
        ListNode *ret=new ListNode(0);
        ListNode *cur=ret;
        int sum=0;

        while(1){
            if(l1!=NULL){
                sum+=l1->val;
                l1=l1->next;
            }
            if(l2!=NULL){
                sum+=l2->val;
                l2=l2->next;
            }
            cur->val=sum%10;  // 该位数字
            sum/=10;  //进位数字
            if(l1!=NULL || l2!=NULL || sum)
                cur=(cur->next=new ListNode(0));   //转入下一个链表节点
            else 
                break;
        }

        return ret;
    }
};


int main()
{
    int t,n;
    Solution s;
    while (cin>>n) {
        ListNode *a = new ListNode(0);
        ListNode *b = new ListNode(0);
        ListNode *pa=a;
        ListNode *pb=b;

        while(n--){
            cin>>t;
            pa=addValAndCreateNewNode(pa,t); //生成链表
        }

        cin>>n;

        while(n--){
            cin>>t;
            pb=addValAndCreateNewNode(pb,t);
        }

        s.addTwoNumbers(a,b); //a,b not release!

    }

    return 0;
}