链表的添加节点，倒置和打印操作

#include <iostream>

using namespace std;

struct Node{
    int data;
    Node * next;
};

class NodeList{
private:
    Node * headnode;
public:
    NodeList(){headnode = 0;}
    ~NodeList();
    Node * nodeReverse();
    Node *  addNode(int curData);
    void printNode();
};

NodeList::~NodeList()
{
    Node * gre;
    while(headnode)
    {
        gre = headnode->next;
        delete headnode;
        headnode = gre;
    }
}
Node * NodeList::nodeReverse()
{
    if (!headnode || !(headnode->next))
    {
        return headnode;
    }
    else
    {
        Node * pre = headnode;
        Node * current = headnode->next;
        while (current)
        {
            Node * post = current->next;
            current->next = pre;
            pre = current;
            current = post;
        }
        headnode->next = NULL;
        headnode = pre;
        return headnode;

    }
}
Node* NodeList::addNode(int curData)
{
    Node * y = new Node;
    y->data = curData;
    y->next = NULL;
    if (!headnode)
    {
        headnode = y;
    }
    else
    {
        Node * p = headnode;
        while (p->next)
        {
            p = p->next;
        }
        p->next = y;
    }
    return headnode;
}

void NodeList::printNode()
{
    Node * p = headnode;
    while (p)
    {
        cout<<p->data<<" ";
        p = p->next;
    }
    cout<<endl;
}

int main()
{
    NodeList py;
    py.addNode(23);
    py.addNode(34);
    py.addNode(45);
    py.addNode(56);
    py.printNode();

    py.nodeReverse();
    py.addNode(89);
    py.printNode();

    return    EXIT_SUCCESS;
}

输出结果