class money_or_others{...};
class _friend{
public:
money_or_others be_betrayed();
.......
.......
};
class man{....};
class shuang{....};
class woman{
public:
shuang make_love(man&);
......
......
};
class woman_frined:public woman,public _friend{
.....
.....
};
typedef woman_friend girl_friend;
//girl_friend's ...??????