关于重载Time类的自增运算符++及注意点

#include<iostream>
using namespace std;
class Time
{
private:
    int hour,minute,second;
public:
    Time(int h,int m,int s);
    friend Time&operator++(Time &t);//返回引用是为了实现连续自增
    void display();
};
Time::Time(int h,int m,int s):hour(h),minute(m),second(s)
{
    if(hour>=24)hour=0;
    if(minute>=60)minute=0;
    if(second>=60)second=0;
}
void Time::display()
{
    cout<<hour<<":"<<minute<<":"<<second<<endl;
}
Time &operator++(Time &t)
{
    ++t.second;
    if(t.second>=60)
    {
        t.second=0;
        ++t.minute;
 &nbs