cout<<"num is :"<<num<<endl; cout<<"name is:"<<name<<endl; cout<<"age is :"<<age<<endl;

这是一段 C++ 代码，使用了标准输出流 cout 来输出变量 num、name、age 的值。其中 << 表示向 cout 输出数据，endl 表示换行符。该代码会在控制台输出以下内容：
num is : [num的值]
name is: [name的值]
age is : [age的值]

请注意，变量 num、name、age 的值需要在代码中进行初始化或赋值才能正常输出。

相关问题

#include <iostream> #include <string> class Person { protected: std::string name; int age; std::string addr; public: void get_value() { std::cout << "请输入姓名："; std::cin >> name; std::cout << "请输入年龄："; std::cin >> age; std::cout << "请输入地址："; std::cin >> addr; } }; class Teacher : public Person { public: void display() { std::cout << "姓名：" << name << std::endl; std::cout << "年龄：" << age << std::endl; std::cout << "地址：" << addr << std::endl; std::cout << "我是教师" << std::endl; } }; class Student : public Person { public: void display() { std::cout << "姓名：" << name << std::endl; std::cout << "年龄：" << age << std::endl; std::cout << "地址：" << addr << std::endl; std::cout << "我是学生" << std::endl; } }; int main() { Teacher t; Student s; s.get_value(); t = s; t.display(); return 0; }并重载operator=

在上面的代码基础上，我们可以为Teacher类重载operator=，使得可以直接将一个Student对象赋值给Teacher对象。代码如下：

#include <iostream>
#include <string>

class Person {
protected:
    std::string name;
    int age;
    std::string addr;
public:
    void get_value() {
        std::cout << "请输入姓名：";
        std::cin >> name;
        std::cout << "请输入年龄：";
        std::cin >> age;
        std::cout << "请输入地址：";
        std::cin >> addr;
    }
};

class Teacher : public Person {
public:
    void display() {
        std::cout << "姓名：" << name << std::endl;
        std::cout << "年龄：" << age << std::endl;
        std::cout << "地址：" << addr << std::endl;
        std::cout << "我是教师" << std::endl;
    }
    Teacher& operator=(const Student& s) {
        this->name = s.name;
        this->age = s.age;
        this->addr = s.addr;
        return *this;
    }
};

class Student : public Person {
public:
    void display() {
        std::cout << "姓名：" << name << std::endl;
        std::cout << "年龄：" << age << std::endl;
        std::cout << "地址：" << addr << std::endl;
        std::cout << "我是学生" << std::endl;
    }
};

int main() {
    Teacher t;
    Student s;
    s.get_value();
    t = s;
    t.display();
    return 0;
}

在Teacher类中，我们重载了operator=，使得可以将一个Student对象s赋值给Teacher对象t。在重载函数中，我们将s的数据成员name、age和addr分别赋值给t的对应成员，并返回一个指向t的引用。在主程序中，我们可以看到，我们仍然先创建了Teacher和Student对象t和s，然后调用s的get_value()函数获取数据，接着将s赋值给t，最后调用t的display()函数输出数据。

优化#include<iostream>using namespace std;class Teacher{protected: string name; int age; char gender; string address; string phone; string title;public: void display(){ cout<<"Name: "<<name<<endl; cout<<"Age: "<<age<<endl; cout<<"Gender: "<<gender<<endl; cout<<"Address: "<<address<<endl; cout<<"Phone: "<<phone<<endl; cout<<"Title: "<<title<<endl; }};class Cadre{protected: string name; int age; char gender; string address; string phone; string post;public: void display(){ cout<<"Name: "<<name<<endl; cout<<"Age: "<<age<<endl; cout<<"Gender: "<<gender<<endl; cout<<"Address: "<<address<<endl; cout<<"Phone: "<<phone<<endl; cout<<"Post: "<<post<<endl; }};class Teacher_Cadre:public Teacher, public Cadre{private: double wages;public: void show(){ Teacher::display(); cout<<"Post: "<<Cadre::post<<endl; cout<<"Wages: "<<wages<<endl; }};int main(){ Teacher_Cadre tc; tc.name="Tom"; tc.age=30; tc.gender='M'; tc.address="Beijing"; tc.phone="123456789"; tc.title="Professor"; tc.post="Manager"; tc.wages=10000; tc.show(); return 0;}

代码本身没有什么问题，但是可以优化一下：

1. 在 Teacher 和 Cadre 类中，有很多重复的属性和方法，可以抽象出一个基类来，减少冗余代码。

2. 在 Teacher 和 Cadre 类中，属性和方法都是 protected 的，可以将它们改为 private ，并添加相应的访问函数（如 getName()、getAge() 等）。

3. 可以使用构造函数来对对象进行初始化，避免在 main 函数中逐个赋值。

优化后的代码如下：

#include <iostream>
#include <string>
using namespace std;

class Person {
protected:
    string name;
    int age;
    char gender;
    string address;
    string phone;
public:
    Person(string n, int a, char g, string addr, string ph) : name(n), age(a), gender(g), address(addr), phone(ph) {}
    string getName() { return name; }
    int getAge() { return age; }
    char getGender() { return gender; }
    string getAddress() { return address; }
    string getPhone() { return phone; }
};

class Teacher : public Person {
private:
    string title;
public:
    Teacher(string n, int a, char g, string addr, string ph, string t) : Person(n, a, g, addr, ph), title(t) {}
    string getTitle() { return title; }
    void display() {
        cout << "Name: " << name << endl;
        cout << "Age: " << age << endl;
        cout << "Gender: " << gender << endl;
        cout << "Address: " << address << endl;
        cout << "Phone: " << phone << endl;
        cout << "Title: " << title << endl;
    }
};

class Cadre : public Person {
private:
    string post;
public:
    Cadre(string n, int a, char g, string addr, string ph, string p) : Person(n, a, g, addr, ph), post(p) {}
    string getPost() { return post; }
    void display() {
        cout << "Name: " << name << endl;
        cout << "Age: " << age << endl;
        cout << "Gender: " << gender << endl;
        cout << "Address: " << address << endl;
        cout << "Phone: " << phone << endl;
        cout << "Post: " << post << endl;
    }
};

class Teacher_Cadre : public Teacher, public Cadre {
private:
    double wages;
public:
    Teacher_Cadre(string n, int a, char g, string addr, string ph, string t, string p, double w) : Teacher(n, a, g, addr, ph, t), Cadre(n, a, g, addr, ph, p), wages(w) {}
    void show() {
        Teacher::display();
        cout << "Post: " << Cadre::post << endl;
        cout << "Wages: " << wages << endl;
    }
};

int main() {
    Teacher_Cadre tc("Tom", 30, 'M', "Beijing", "123456789", "Professor", "Manager", 10000);
    tc.show();
    return 0;
}