【c++】多层次继承类对象的构造函数参数的传递方法

#include <iostream.h>
//基类CBase
class CBase
{
    int a;
public:
    CBase(int na)
    {
        a=na;
        cout<<"CBase constructor! ";
    }
    ~CBase(){cout<<"CBase deconstructor! ";}
    int GetA(){return a;}
};

//CBase的派生类CDerive
class CDerive : public CBase
{
    int b;
public:
    //将参数na传递给基类CBase
    CDerive(int nb,int na):CBase(na)
    {
        b=nb;
        cout<<"CDerive constructor! ";
    }
    ~CDerive(){cout<<"CDerive deconstructor! ";}
    int GetB(){return b;}
};
//CDerive的派生类CSubDerive
class CSubDerive : public CDerive
{
    int c;
public:
    //向直接基类传递参数,不负责向间接基类传递参数
    CSubDerive(int nc,int nb,int na):CDerive(nb,na)    
    {    
        c=nc;
        cout<<"CSubDerive constructor! ";
    }
    ~CSubDerive(){cout<<"CSubDerive deconstructor! ";}
    int GetC(){return c;}
    void show()
    {
        //因为是公有继承,子派生类可以访问其父类和父类的父类的公有成员函数
        cout<<"int the subderive class object : ";
        cout<<"a = "<<GetA()<<endl;
        cout<<"b = "<<GetB()<<endl;
        cout<<"c = "<<GetC()<<endl;
    }
};

void main()
{
    CSubDerive obj(30,20,10);

    cout<<"call the display function of the object: ";
    obj.show();

    cout<<" call the interface function of the object: ";
    cout<<"a = "<<obj.GetA()<<endl;
    cout<<"b = "<<obj.GetB()<<endl;
    cout<<"c = "<<obj.GetC()<<endl;    
}
     
     
分析：
1.运行结果如下：