为什么这个程序没有编译

Question

#include <iostream>
class Abc // created class with name Abc
{
    void display()//member function
    {
        cout<<"Displaying NO."<<endl;
    }
};
int main()
{
    Abc obj;//creating object of the class
    obj.display();//calling member function inside class
}

它返回错误为

main.cpp: In function 'int main()':
main.cpp:5:10: error: 'void Abc::display()' is private
     void display()
          ^
main.cpp:13:17: error: within this context
     obj.display();
                 ^

我试图使显示功能,public int main但它给出了错误

main.cpp:5:11: error: expected ':' before 'void'
    public void display()
           ^

Answer 1

声明为:

class Abc
{
public:

    void display()
    {
        cout<<"Displaying NO."<<endl;
    }
};

要么:

struct Abc
{
    void display()
    {
        cout<<"Displaying NO."<<endl;
    }
};

struct的默认保护是公共的,类的默认保护是私有的