[LeetCode]AddTwoNumbers

You are given two linked lists representing two non-negative numbers. 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.

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

代码：

// AddTwoNumbers.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include<iostream>
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 *res,*p;
		int plus = 0,sum=0;
		res = new ListNode(0);
		p = res;
		while (l1 != NULL&&l2 != NULL)
		{
			sum = l1->val + l2->val+plus;
			//p = new ListNode(sum % 10);
			p->val = sum % 10;
			plus = sum / 10;
			
			l1 = l1->next;
			l2 = l2->next;
			if (l1 != NULL&&l2 != NULL)
			{
				ListNode *temp = new ListNode(0);
				p->next = temp;
				p = p->next;
			}
		}
		if (l1 == NULL&&l2 == NULL)
		{
			if (plus != 0)
			{
				ListNode *temp = new ListNode(plus);
				p->next = temp;
				p = p->next;
			}
		}
		else if (l1 == NULL)
		{
			while (l2 != NULL)
			{
				sum =l2->val + plus;
				ListNode *temp = new ListNode(sum % 10);
				plus = sum / 10;
				p->next = temp;
				p = p->next;
				l2 = l2->next;
			}
			if (plus != 0)
			{
				ListNode *temp = new ListNode(plus);
				p->next = temp;
				p = p->next;
			}

		}
		else if (l2 == NULL)
		{
			while (l1 != NULL)
			{
				sum = l1->val + plus;
				ListNode *temp = new ListNode(sum % 10);
				plus = sum / 10;
				p->next = temp;
				p = p->next;
				l1 = l1->next;
			}
			if (plus != 0)
			{
				ListNode *temp = new ListNode(plus);
				p->next = temp;
				p = p->next;
			}

		}
		return res;
	}
};

int _tmain(int argc, _TCHAR* argv[])
{
	ListNode *l1 = new ListNode(1);
	//ListNode *l2 = new ListNode(4);
	//ListNode *l3 = new ListNode(3);
	//l1->next = l2;
	//l2->next = l3;

	ListNode *ll1 = new ListNode(9);
	ListNode *ll2 = new ListNode(9);
	//ListNode *ll3 = new ListNode(4);
	ll1->next = ll2;
	//ll2->next = ll3;

	Solution ss;
	ListNode *res = ss.addTwoNumbers(l1,ll1);
	while (res != NULL)
	{
		cout << res->val << "";
		res = res->next;
	}
	system("pause");
	return 0;
}