#define _CRT_SECURE_NO_WARNINGS //windows系统

#include <iostream>

#include <cstdlib>

#include <cstring>

using namespace std;

class student

{

private:

    char *name;

    int age;

public:

    student(const char *n = "no name", int a = ) 　　

    {

        name = new char[];                 // 比malloc好!

        strcpy(name, n);

        age = a;

        cout << "构造函数，申请了100个char元素的动态空间" << endl;

    }

    student & operator=(const student &s)

    {

        strcpy(name, s.name);

        age = s.age;

        cout << "赋值函数，保证name指向的是自己单独的内存块" << endl;

        return *this;    //返回 “自引用”

    }

    student(const student &s)

    {               // 拷贝构造函数 Copy constructor

        name = new char[];

        strcpy(name, s.name);

        age = s.age;

        cout << "拷贝构造函数，保证name指向的是自己单独的内存块" << endl;

    }

    void display(void)

    {

        cout << name << ", age " << age << endl;

    }

　　virtual ~student()

    {                             // 析构函数

        cout << "析构函数，释放了100个char元素的动态空间" << endl;

        delete[] name;                          // 不能用free!

    }

};

int main()

{

    //student s;    //编译错误，类中实现了构造函数，因此，需要有参数

    student k("John", );

    student mm(k);        //拷贝构造函数

    student m("lill", );

    m.display();

    m = k;                //赋值函数

    k.display();

    mm.display();

    return ;

}