c ++编译器错误中的简单类继承

Question

我希望我的Dog类正确地继承Pet中的函数，以便main中的代码能够正确执行。编译器警告从基类Pet。

调用私有方法

主：

Dog * d = new Dog( "Muffin" );

cout << "The " << d->getVariety( ) << " " << d->getName( ) << " speaks by saying " << d->speak( ) << endl;

类：

class Pet
{
public:
Pet( );
Pet( std::string name, std::string variety, std::string says )
{

    myName=name;
    myVariety=variety;
    howIspeak=says;
}

std::string getName( ) const
{
    return myName;
};
public:
std::string getVariety( ) const
{
    return myVariety;
};

std::string speak() const
{

    return howIspeak;
};

protected:
std::string myName;
std::string myVariety;
std::string howIspeak;
};

class Dog: Pet
{
public:
Dog( );
Dog( std::string name );

virtual void speak( );
};

Answer 1

C ++默认为私有继承。因此使用

class Dog: public Pet

Answer 2

默认情况下，

类具有私有继承

 class Dog: public Pet