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)
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
题目的意思就是实现链表的加法
2+5 = 7
4+6 = 1,0 进位
3+4+1=8 (1是进位产生的)
自己加了main函数做测试
#include <iostream>
using namespace std;
//默认关于链表的定义
struct ListNode {
int val;
ListNode *next;
ListNode(int x) : val(x), next(NULL) {}
};
class Solution {
public:
ListNode *addTwoNumbers(ListNode *l1, ListNode *l2) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
ListNode rootNode(0);
ListNode *pCurNode = &rootNode;
int forward = 0;//进位
while(l1||l2)
{
int v1 = (l1 ? l1->val : 0);
int v2 = (l2 ? l2->val : 0);
int sum = v1 + v2 + forward;
//处理进位
forward = sum / 10;
sum = sum % 10;
ListNode *pNode = new ListNode(sum);
pCurNode->next = pNode;
pCurNode = pNode;
if(l1) l1 = l1->next;
if(l2) l2 = l2 ->next;
}
//处理最后有进位
if(forward > 0)
{
ListNode *pNode = new ListNode(forward);
pCurNode->next = pNode;
}
return rootNode.next;
}
};
int main()
{
ListNode l1(2);
ListNode x2(4);
ListNode x3(3);
l1.next = &x2;
x2.next = &x3;
ListNode l2(5);
ListNode y2(6);
ListNode y3(4);
l2.next = &y2;
y2.next = &y3;
//ListNode l3 = new ListNode(6);
Solution so;
ListNode *ret = so.addTwoNumbers(&l1, &l2);
do{
cout<<ret->val;
cout<<" ";
ret = ret->next;
}
while(ret != NULL);
return 0;
}