c++ - 删除链表中的节点

Question

您好，我正在尝试删除链接列表中的节点。我首先尝试如何删除头节点和尾节点。头部删除似乎有效，但尾部删除不起作用。当我运行代码时，尾部原来所在的位置被垃圾值替换。谁能弄清楚为什么吗？非常感谢!

void CList :: Remove() {

    int data = NULL;

    std::cout<<"Enter value you wish to remove ";
    std:: cin>> data;

    cNode *pMyPointer = m_pHead;

    while (pMyPointer != NULL)
    {
        if (pMyPointer->m_nValue == data) {
            std::cout << "Element found";
            goto del;
        }

        else {
            pMyPointer = pMyPointer->m_pNext;
        }   
    }

    del:

    //removing the head
    if (pMyPointer == m_pHead)
        m_pHead= m_pHead->m_pNext;
    //removing the tail
    else if (pMyPointer == m_pTail)
        m_pTail = m_pTail->m_pPrev;

    delete pMyPointer;
}

Answer 1

考虑node_1指向node_2(只是2节点的情况) 看看这段代码

else if (pMyPointer == m_pTail)
        m_pTail = m_pTail->m_pPrev;

node_1 指向node_2 。它仍然指向那里。一旦删除了node_2，node_1仍将指向node_2(或删除node_2后成为垃圾)，因此您必须确保node_1指向NULL。即最后一个但应该指向 null 。

类似的东西

else if (pMyPointer == m_pTail)
    m_pTail->m_pPrev->next=NULL;
    m_pTail = m_pTail->m_pPrev;