面试题14:反转链表

2015-11-21 01:27:46 · 作者: · 浏览: 8

\


#include "stdafx.h"   
#include    
using namespace std;  
  
struct ListNode  
{  
    int m_nValue;  
    ListNode *m_pNext;  
};  
  
ListNode *ReverseList(ListNode *pListHead)  
{  
    if (pListHead == NULL)  
    {  
        return NULL;  
    }  
  
    ListNode *pReverseHead = NULL;  
    ListNode *pPre = NULL;  
    ListNode *pNode = pListHead;  
    ListNode *pNext = NULL;  
  
    while (pNode != NULL)  
    {  
       pNext = pNode->m_pNext;  
       if (pNext == NULL)  
       {  
           pReverseHead = pNode;             
       }  
       pNode->m_pNext = pPre;  
       pPre = pNode;  
       pNode = pNext;  
    }  
    return pReverseHead;  
}  
  
//创建一个链表,输入从头到尾结点的值,输入-1表示结束   
void CreateList(ListNode *& pHead)  
{     
    ListNode *pListNode = NULL;  
    ListNode *pCurLastNode = NULL;  
    bool isHead = true;  
  
    while (1)  
    {  
        if (isHead)  
        {     
            pHead = new ListNode();  
            cin >> pHead->m_nValue;  
            pHead->m_pNext = NULL;  
            isHead = false;  
            pCurLastNode = pHead;  
        }  
        else  
        {  
            pListNode = new ListNode();  
            cin >> pListNode->m_nValue;  
            if (pListNode->m_nValue == -1)  
            {  
                break;  
            }  
            pListNode->m_pNext = NULL;  
            pCurLastNode->m_pNext = pListNode;  
            pCurLastNode = pListNode;     
        }             
    }  
}  
  
//从头到尾打印链表   
void PrintList(ListNode *&pHead)  
{  
    if (pHead != NULL)  
    {  
        ListNode *pCur = pHead;  
        while (pCur != NULL)  
        {  
            cout << pCur->m_nValue << " ";  
            pCur = pCur->m_pNext;  
        }  
        cout << endl;  
    }  
    else  
    {  
        cout << "链表为空!" << endl;  
    }  
}  
  
int _tmain(int argc, _TCHAR* argv[])  
{  
    ListNode *pListHead = NULL;  
    CreateList(pListHead);  
    PrintList(pListHead);  
    ListNode *pReverseHead = ReverseList(pListHead);  
    cout << pReverseHead->
m_nValue << endl; PrintList(pReverseHead); system("pause"); return 0; } #include "stdafx.h" #include using namespace std; struct ListNode { int m_nValue; ListNode *m_pNext; }; ListNode *ReverseList(ListNode *pListHead) { if (pListHead == NULL) { return NULL; } ListNode *pReverseHead = NULL; ListNode *pPre = NULL; ListNode *pNode = pListHead; ListNode *pNext = NULL; while (pNode != NULL) { pNext = pNode->m_pNext; if (pNext == NULL) { pReverseHead = pNode; } pNode->m_pNext = pPre; pPre = pNode; pNode = pNext; } return pReverseHead; } //创建一个链表,输入从头到尾结点的值,输入-1表示结束 void CreateList(ListNode *& pHead) { ListNode *pListNode = NULL; ListNode *pCurLastNode = NULL; bool isHead = true; while (1) { if (isHead) { pHead = new ListNode(); cin >> pHead->m_nValue; pHead->m_pNext = NULL; isHead = false; pCurLastNode = pHead; } else { pListNode = new ListNode(); cin >> pListNode->m_nValue; if (pListNode->m_nValue == -1) { break; } pListNode->m_pNext = NULL; pCurLastNode->m_pNext = pListNode; pCurLastNode = pListNode; } } } //从头到尾打印链表 void PrintList(ListNode *&pHead) { if (pHead != NULL) { ListNode *pCur = pHead; while (pCur != NULL) { cout << pCur->m_nValue << " "; pCur = pCur->m_pNext; } cout << endl; } else { cout << "链表为空!" << endl; } } int _tmain(int argc, _TCHAR* argv[]) { ListNode *pListHead = NULL; CreateList(pListHead); PrintList(pListHead); ListNode *pReverseHead = ReverseList(pListHead); cout << pReverseHead->m_nValue << endl; PrintList(pReverseHead); system("pause"); return 0; }

?