单链表快速排序

#include<iostream>
#include <time.h>
using namespace std;

//定义链表节点
struct _tNode
{
    int nValue;
    _tNode* pNext;

    _tNode(){memset(this , 0 , sizeof(_tNode));}
};

////////////////////////////////////
//单链表快速排序
///////////////////////////////////
void quickSort(_tNode* pBegin , _tNode* pEnd)
{
    if(NULL == pBegin 
        || NULL == pEnd
        || pBegin == pEnd)
    {
        return;
    }

    _tNode* pFirst = pBegin;
    _tNode* pSecond = pFirst->pNext;
    
    int nMidValue = pBegin->nValue;

    //开始排序
    while(pSecond != pEnd->pNext && pSecond != NULL)
    {
        if(pSecond->nValue < nMidValue)
        {
            pFirst = pFirst->pNext;
            std::swap(pFirst->nValue , pSecond->nValue);
        }

        pSecond = pSecond->pNext;
    }

    //更换支点后完成1轮排序
    std::swap(pBegin->nValue , pFirst->nValue);

    quickSort(pBegin , pFirst);
    quickSort(pFirst->pNext , pEnd);//此处的next很重要,不然将导致死循环
}

void main()
{
    srand(static_cast<unsigned int>(time(NULL)));
    const int nNodeCnt = 10;
    _tNode* pHead = new _tNode();
    _tNode* pLastNode = pHead;

    //构造一个链表
    for(int nCnt = 0; nCnt < nNodeCnt; ++nCnt)
    {
        _tNode* pNode = new _tNode();
        pNode->nValue = rand() % 10;

        pLastNode->pNext = pNode;
        pLastNode = pNode;
    }

    
    //查看未排序前的输出
    pLastNode = pHead;
    for(int nCnt = 0; nCnt < nNodeCnt; ++nCnt)
    {
        _tNode* pNode = pLastNode->pNext;
        pLastNode = pNode;
        cout<<pNode->nValue<<endl;
    }
    cout<<endl;

    //查看排序输出
    quickSort(pHead , pHead + nNodeCnt);
    pLastNode = pHead;
    for(int nCnt = 0; nCnt < nNodeCnt; ++nCnt)
    {
        _tNode* pNode = pLastNode->pNext;
        pLastNode = pNode;
        cout<<pNode->nValue<<endl;
    }

    pLastNode = pHead;
    //删除包含HEAD以内的11个节点
    for(int nCnt = 0; nCnt <= nNodeCnt; ++nCnt)
    {
        _tNode* pNode = pLastNode;
        pLastNode = pNode->pNext;
        delete pNode;
    }

    system("pause");
}