LeetCode Add Two Numbers(用链表模拟加法)

题目链接：

传送门

Code:

#include <bits/stdc++.h>

using namespace std;

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

class Solution {
public:
    ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
        ListNode *head=NULL,*p=NULL;
        int val=0;
        while(l1!=NULL||l2!=NULL||val){
            int left=val;
            if(l1!=NULL){
                left+=l1->val,l1=l1->next;
            }
            if(l2!=NULL){
                left+=l2->val,l2=l2->next;
            }
            val=left/10;
            left=left%10;
            ListNode* tmp = new ListNode(left);
            if(!head)
                head=tmp;
            if(p)
                p->next=tmp;
            p=tmp;
        }
        return head;
    }
};

int main()
{
    ListNode *l1,*l2,*l3;
    l1=new ListNode(99);
    l3=new ListNode(99);
    Solution fuck;
    ListNode *ans = fuck.addTwoNumbers(l1,l3);
    while(ans!=NULL){
        cout<<ans->val;
        ans=ans->next;
    }
    puts("");
    return 0;
}