#include<iostream.h>
//定義最低層基類First，它作為其他類的基類
class First {
    int val1;
public:
    First() {
        cout<<"The First initialized"<<endl;
    }
    ~First() {
        cout<<"The First destroyed"<<endl;
    }
};
//定義派生類Second，它作為其他類的基類
class Second :public First {   //默認為private模式
    int val2;
public:
    Second() {
        cout<<"The Second initialized"<<endl;
    }
    ~Second() {
        cout<<"The Second destroyed"<<endl;
    }
};
//定義最上層派生類Three
class Three :public Second {
    int val3;
public:
    Three() {
        cout<<"The Three initialized"<<endl;
    }
    ~Three() {
        cout<<"The Three destroyed"<<endl;
    }
};
//main()函數中測試構造函數和析構函數的執行情況
main() { 
    Three t1;
    cout<<"---- Use the t1----"<<endl;
}