C++day4 - 技术栈

1.思维导图

2.设计一个Per类，类中包含私有成员:姓名、年龄、指针成员身高、体重，再设计一个Stu类，类中包含私有成员:成绩、Per类对象p1，设计这两个类的构造函数、析构函数和拷贝构造函数、拷贝赋值函数。

cpp 复制代码
#include <iostream>

using namespace std;
class Per
{
    friend class Stu;
private:
    string name;
    int age;
    int *height;
    int *weight;
public:
    Per()//per的无参构造函数
    {
        cout  <<"Per的无参构造函数" << endl;
    }
    Per(string name,int age,int height,int weight):name(name),age(age),height(new int(height)),weight(new int(weight))//Per的有参构造函数,并使用初始化列表初始化
    {
        cout << "Per的有参构造函数" << endl;
    }
    Per(const Per &other):name(other.name),age(other.age),height(new int (*other.height)),weight(new int (*other.weight))//Per的拷贝构造函数
    {
        cout << "Per的拷贝构造函数" << endl;
    }
    Per &operator=(const Per &other)//Per的拷贝赋值函数
    {
        if(this!=&other)//避免自己给自己赋值
        {
            name=other.name;
            age=other.age;
            height=new int(*(other.height));
            weight=new int(*(other.weight));
        }
        cout << "Per的拷贝赋值函数" <<endl;
        return *this;
    }
    ~Per()
    {
        cout << "Per的析构函数" << endl;
        delete weight;
        delete height;
        weight=nullptr;
        height=nullptr;

    }
    void show()
    {
        cout << name  << " " << age << " " << *height << " " << *weight << endl;
    }
};

class Stu
{
private:
    double score;
    Per p1;
public:
    Stu()//Stu的无参构造函数
    {
         cout << "Stu的无参构造函数" << endl;

    }
    Stu(double score,Per &p1):score(score),p1(p1)//Stu的有参构造函数
    {
        cout << "Stu的有参构造函数" << endl;
    }
    Stu(const Stu &other):score(other.score),p1(other.p1)//Stu的拷贝构造函数
    {
        cout << "Stu的拷贝构造函数" << endl;
    }
    Stu &operator=(const Stu &other)//Stu的拷贝赋值函数
    {
        if(this!=&other)
        {
            score=other.score;
            p1=other.p1;
        }
        return *this;
        cout << "Stu的拷贝赋值函数" << endl;
    }
    ~Stu()
    {
         cout << "Stu的析构函数" << endl;
    }
    void show()
    {
        cout << score << " " <<p1.name  << " " << p1.age << " " << *p1.height << " " << *p1.weight << endl;//这里要访问Per类里private里的成员所以要在Per类增加友元
    }
};
int main()
{
    Per s1;//调用Per无参构造函数
    Per s2("张三",18,180,75);//调用Per有参构造函数
    Per s3(s2);//调用Per的拷贝构造函数
    Per s4;
    s4=s3;//调用Per的拷贝赋值函数
    s4.show();
    cout << "--------------------------------" << endl;
    Stu b1;//stu无参构造函数
    Stu b2(100,s2);//stu有参构造函数
    Stu b3(b2);//stu拷贝构造函数
    Stu b4;
    b4=b3;//stu拷贝赋值函数
    b4.show();

    return 0;
}