简单的C++链表类

#include<iostream>
using namespace std;


class CList
{
private:
    struct Node
    {
        int nValue;
        Node* pNext;
    };
    Node* m_pHead;
    Node* m_pEnd;
    int m_nSize;
public:
    CList()
    {
        m_pHead = 0;
        m_pEnd = 0;
        m_nSize = 0;
    }
    ~CList()
    {
        Node* pDel = NULL;
        while(m_pHead)
        {
            pDel = m_pHead;
            m_pHead = m_pHead->pNext;
            delete pDel;
            pDel = NULL;
        }
    }
public:
    void Push_Back(int nVal)
    {
        //  需要一个节点
        Node* pNode = new Node;
        pNode->nValue = nVal;
        pNode->pNext = NULL;
        //  放到链表上
        if(m_pHead == NULL)
        {
            m_pHead = pNode;
            m_pEnd = pNode;
        }
        else
        {
            m_pEnd->pNext = pNode;
            m_pEnd = pNode;
        }
        m_nSize++;
    }
    void Pop_Front()  // 在头删除
    {
        if(m_pHead == 0)  //  没有节点
            return ;

        if(m_pHead == m_pEnd) //  一个节点
        {
            delete m_pHead;
            m_pHead = 0;
            m_pEnd = 0;
            m_nSize = 0;
            return ;
        }

        //  多个节点
        Node* pDel = m_pHead;
        m_pHead = m_pHead->pNext;
        delete pDel;
        pDel = NULL;
        m_nSize--;
    }
    void Pop_Back()  // 在头删除
    {
        if(m_pHead == 0)  //  没有节点
            return ;

        if(m_pHead == m_pEnd) //  一个节点
        {
            delete m_pHead;
            m_pHead = 0;
            m_pEnd = 0; 
            m_nSize = 0;
            return ;
        }

        //  多个节点
        Node* pDel = m_pHead;
        while(pDel->pNext->pNext != NULL)
            pDel = pDel->pNext;

        delete m_pEnd;
        m_pEnd = pDel;
        m_pEnd->pNext = 0;
        m_nSize--;
    }
    void Show()
    {
        Node* pTemp = m_pHead;
        while(pTemp)
        {
            cout << pTemp->nValue << " ";
            pTemp = pTemp->pNext;
        }
    }
};


int main()
{
    CList lst1;
    lst1.Show();
    cout << endl << "=================================" << endl;


    system("pause");
    return 0;
}