C++友元函数访问私有成员

#include<iostream>using namespace std;class CTimeInfo{public:void setTime();//默认函数构造void setTime(int newH,int newM)//带参数的成员函数构造{hour=newH;minute=newM;}void showTime(){cout<<hour<<":"<<minute<<endl;}private:int hour,minute;friend void showtime12(CTimeInfo);//友元函数定义,括号里加上类名称friend void showtime24(CTimeInfo);//友元函数定义,括号里加上类名称};void CTimeInfo::setTime()//默认函数在类外初始化{hour=0;minute=0;}void showtime12(CTimeInfo x)//友元函数实现,注意括号里的格式,以及函数体引用私有成员的格式{cout<<(x.hour)%12<<":"<<x.minute<<endl;}void showtime24(CTimeInfo x){cout<<x.hour<<":"<<x.minute<<endl;}int main(){CTimeInfo t1,t2;t1.setTime();t1.showTime();showtime12(t1);showtime24(t1);t2.setTime(15,20);showtime12(t2);showtime24(t2);return 0;}