How to utilize classes in C++?

To use classes in C++, the following steps need to be taken:

1. category

class MyClass {
public:
    // 成员变量
    int myVar;
    
    // 成员函数
    void myFunction();
};

1. Class name::function name

void MyClass::myFunction() {
    // 函数的实现代码
}

1. class name object name

MyClass obj;

1. Can you please explain why you arrived late?
   Why did you come late?

obj.myVar = 42; // 访问成员变量
obj.myFunction(); // 调用成员函数

The complete example code is as follows:

#include <iostream>

class MyClass {
public:
    int myVar;
    
    void myFunction() {
        std::cout << "Hello, World!" << std::endl;
    }
};

int main() {
    MyClass obj;
    obj.myVar = 42;
    obj.myFunction();
    
    return 0;
}

This is a simple example of using a class that you can extend and modify the member variables and member functions according to your needs.