题解 | #输出单向链表中倒数第k个结点#

#include<iostream>
using namespace std;
struct ListNode
{
  int m_nKey;
  ListNode *m_pNext;
  ListNode(int k):m_nKey(k),m_pNext(NULL){}
};
int main()
{
    int n;
    while(cin>>n)
    {
        ListNode *pHead=NULL;
        ListNode *pTempHead=NULL;
        while(n--)
        {
            int d;
            cin>>d;
            ListNode *pNode=new ListNode(d);
            if(pHead==NULL)
            {
                pHead=pNode;
                pTempHead=pHead;
            }
            else
            {
                pTempHead->m_pNext=pNode;
                pTempHead=pNode;
            }
        }
        int k;
        cin>>k;
        pTempHead=pHead;
        while(k--&&pTempHead)
        {
            pTempHead=pTempHead->m_pNext;
        }
        while(pHead&&pTempHead)
        {
            pHead=pHead->m_pNext;
            pTempHead=pTempHead->m_pNext;
        }
        if(pHead)
        {
            cout<<pHead->m_nKey<<endl;
        }
        else
        {
            cout<<NULL<<endl;
        }
    }
    return 0;
}