c++，类的组合

#include <iostream>
using namespace std;
#include <string>
//--------------------------------------
class A
{
public:
    int m_ax ;
    int m_ay ;

    A();
    A(int val,int vy);
};
A::A()
{

}
A::A(int vx,int vy)
{
    this->m_ax = vx;
    this->m_ay = vy;
}
//--------------------------------------
class B
{
public:
    int m_bx ;

    B();
    B(int val);
};

B::B()
{

}
B::B(int val)
{
    this->m_bx = val;
}
//--------------------------------------
class C
{
public:
    A ac;
    B bc;
    C();
    C(int vax,int vay,int vbx );
    C(int vax ,int vay);
    C(int vbx) ;
    

    void show();
};
C::C()
{

}
C::C(int vax ,int vay,int vbx)
    :ac(vax,vay),bc(vbx)
{

}
C::C(int vax ,int vay)
    :ac(vax,vay)
{

}

C::C(int vbx):bc(vbx)//没有初始化的内部类对象，可以不写出来 ，也可以写出来ac()。     C::C(int vbx):bc(vbx),ac()

{

}
void C::show()
{
    cout<<"ac.m_ax = "<<ac.m_ax<<endl;
    cout<<"ac.m_ay = "<<ac.m_ay<<endl;
    cout<<"bc.m_bx = "<<bc.m_bx<<endl;
}
//--------------------------------------
int main()
{
     C c1(1 ,2 ,3 );
     c1.show();
    while(1);
    return 0 ;
}
// ac.m_ax = 1
// ac.m_ay = 2
// bc.m_bx = 3