11-11 继承

虚函数 多态

出现菱形继承，上两条表用虚拟继承，其他两条边随意
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#include<iostream>
using namespace std;
class person 
{
public:
    int id;
};
class father:virtual public person   //
{
public:
    father(){id=30;}
    void money()
    {
        cout<<"money"<<endl;
    }
};
class mother:virtual public person  //
{
public:
    mother(){id=20;}
    void face()
    {
        cout<<"漂亮，高"<<endl;
    }
};
class son:public mother,public father
{
    
};
int main()
{
    son s;
    s.id;                //为什么打印的是后者的id？？？
    cout<<s.id<<endl;
}

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