数据结构-＞链栈（c++）

typedef struct Node {
    date_t date;
    Node* next;
};
class Liststack {
public:
    Liststack()
    {
        top = nullptr;
    }
    ~Liststack();
    void push_back(date_t date);
    bool isEmpty();
    date_t pop();
    date_t viewtop();
    
private:
    Node* top;
};
Liststack:: ~Liststack()
{
    while (top != nullptr)
    {
        Node* temp = top;
        top = top->next;
        delete temp;
    }
}
void Liststack:: push_back(date_t date)
{
    Node* new_list = new Node;
    new_list->date = date;
    new_list->next = top;
    top = new_list;
}
bool Liststack::isEmpty()
{
    return top == nullptr;
}
date_t Liststack::pop()
{
    date_t temp = top->date;
    Node* ptem = top;
    top = top->next;
    delete ptem;
    return isEmpty()?-1:temp;
}
date_t Liststack::viewtop()
{
    return isEmpty()?-1:top->date;
}
void stackx()
{
    Liststack list;
    while (true) {
        cout << "\n栈操作：" << endl;
        cout << "1. 压入元素" << endl;
        cout << "2. 弹出元素" << endl;
        cout << "3. 查看栈顶元素" << endl;
        cout << "4. 获取栈的大小" << endl;
        cout << "5. 判断栈是否为空" << endl;
        int choice;
        cout << "请选择操作：";
        cin >> choice;
        switch (choice)
        {
        case 1:
            cout << "请输入插入元素" << endl;
            date_t re;
            cin >> re;
            list.push_back(re);
            break;
        case 2:
            cout << list.pop() << endl;
            break;
        case 3:
            cout << list.viewtop() << endl;
            break;
        case 4:

            break;
        case 5:
            list.isEmpty();
            break;
        default:
            break;
        }
    }
}