使用继承的受保护成员时出现问题(C++)

这是真的 Warrior 没有成员 m_damage Soldier 只有 士兵

你应该允许 s构造函数将损坏参数作为参数,并传递所需的值 m_损坏

#include <iostream>

class Soldier{
protected:
    const int m_damage;
public:
    // explicit will prevent implicit conversions from 
    // being permitted when constructing Soldier
    // see http://en.cppreference.com/w/cpp/language/explicit
    explicit Soldier(int damage=5):
        m_damage(damage)
    {}

    int damage() const
    {
        return m_damage;
    }
};

class Warrior: public Soldier{
public:
    Warrior()
        :  Soldier(10)
    {}
};

// lets make another subclass which implicitly uses the 
// default Soldier constructor.
class Samurai: public Soldier{
public:
    Samurai()
    {}
};

int main(){
    Warrior w;
    Samurai s;

    std::cout << w.damage() << '\n';
    std::cout << s.damage() << '\n';
}