LinkedList C++中的指针问题

Question

因此，我尝试将java版本的链表移植到c++，但使用指针指向正确的对象时遇到了很大困难。移除遍历和反向遍历的目标是简单地按顺序打印出链表的值，然后按相反的顺序打印。这是代码。我之所以发布大部分内容而不是某些部分，是因为我相信你需要它的上下文

控制台输出：他们是平等的已删除5穿过-858993460

它打印出它们是相等的，因为它在remove（data）中while循环的第一次迭代时立即中断。

#include <iostream>
#include <string>
#include <string.h>
using namespace std;
class Node{
public:
    int data;
    Node *pNext;

    Node();
    Node(int x);
};
Node::Node(){
    data = NULL;
    pNext = NULL;
}
Node::Node(int x){
    data = x;
    pNext = NULL;
}
class List{
private: 
    Node *head = NULL;
public:
    void insert(int data){
        Node temp(data);
        temp.pNext = head;
        head = &temp;

    }
    Node removeHead(){
        if (head != NULL){
            Node *temp = head;
            head = head->pNext;
            return *temp;
        }
        else{
            cout << "Empty List" << endl;
        }
        return NULL;
    }

    Node remove(int data){
        Node *previousLink = head;
        Node *currentLink = head;
        while (currentLink->data != data){
            if (currentLink == currentLink->pNext){
                cout << "They are equal" << endl;
                break;
            }
            previousLink = currentLink;
            if (currentLink->data == NULL)
            currentLink = currentLink->pNext;
            cout << "Current " << currentLink->data << " Previous " 
            << previousLink->data <<endl;
        }
        if (head->data == data){
            head = head->pNext;
        }
        else{
            previousLink->pNext = currentLink->pNext;
        }
        return *currentLink;
    }
    void traverse(){
        traverse(head);
    }
    void reverseTraverse(){
        reverseTraverse(head);
    }

private:
    void traverse(Node *link){
        cout << link->data << endl;
        if (link != link->pNext)
            traverse(link->pNext);
    }
    void reverseTraverse(Node *link){
        if (link != link->pNext)
            traverse(link->pNext);
        cout << link->data << endl;
    }

};
int main(){
    cout << " Hello Worldn";
    List list;

    for (int i = 0; i <= 9; ++i)
        list.insert(i);
    list.remove(5);
    cout << "removed 5n";
    cout << "traverse" << endl;
    list.traverse();
    cout << "reverse" << endl;
    list.reverseTraverse();
    system("PAUSE");
    return 0;

}

Answer 1

您的问题是，如果您说：

Node temp(data);

那么它只是一个局部变量，它将在封闭函数（例如insert函数）结束后消失。请改用new，然后在删除时将其删除。

顺便说一句，你不需要List类。节点就是列表。