第9周项目2-Time类中的运算符重载（续）

#include<iostream>using namespace std;class CTime{private:    unsigned short int hour;    // 时    unsigned short int minute;  // 分    unsigned short int second;  // 秒public:    CTime(int h=0,int m=0,int s=0);    void setTime(int h,int m,int s)    {        second=s;        minute=m;        hour=h;    }    void display();    //二目的比较运算符重载    bool operator > (CTime &t);    bool operator < (CTime &t);    bool operator >= (CTime &t);    bool operator <= (CTime &t);    bool operator == (CTime &t);    bool operator != (CTime &t);    //二目的加减运算符的重载    //返回t规定的时、分、秒后的时间    //例t1(8,20,25),t2(11,20,50)，t1+t2为19:41:15    CTime operator+(CTime &t);    CTime operator-(CTime &t);//对照+理解    CTime operator+(int s);//返回s秒后的时间    CTime operator-(int s);//返回s秒前的时间    //二目赋值运算符的重载    CTime operator+=(CTime &c);    CTime operator-=(CTime &c);    CTime operator+=(int s);//返回s秒后的时间    CTime operator-=(int s);//返回s秒前的时间    CTime operator++(int);//后置++，下一秒    CTime operator++();//前置++，下一秒，前置与后置返回值不一样    CTime operator--( int);//后置--，前一秒    CTime operator--();//前置--，前一秒    friend istream &operator>>(istream &input,  CTime &t);    friend ostream &operator<<(ostream &output, CTime t);};CTime::CTime(int h,int m,int s){    hour=h;    minute=m;    second=s;}istream &operator>>(istream &cin,CTime &t){    char ch1,ch2;    cout<<"请输入时间(hh:mm:ss) ";    while(1)    {        cin>>t.hour>>ch1>>t.minute>>ch2>>t.second;        if (ch1==':'&&ch2==':')            break;        cerr<<"时间格式不正确! 请重新输入\n";    }    return cin;}// 重载输出运算符<<ostream &operator<<(ostream &out,CTime t){    out<<t.hour<<':'<<t.minute<<':'<<t.second;    return out;}bool CTime::operator>(CTime &t) // 判断时间t1>t2{    if (hour>t.hour)        return true;    if (hour<t.hour)        return false;    if (minute>t.minute)        return true;    if (minute<t.minute)        return false;    if (second>t.second)        return true;    return false;}bool CTime::operator < (CTime &t)// 判断时间t1<t2{    if (hour<t.hour)        return true;    if (hour>t.hour)        return false;    if (minute<t.minute)        return true;    if (minute>t.minute)        return false;    if (second<t.second)        return true;    return false;}bool CTime::operator<=(CTime &t){    return !(*this > t);}bool CTime::operator>=(CTime &t){    return !(*this<t);}bool CTime::operator==(CTime &t){    return !((*this<t)||(*this<t));}bool CTime::operator!=(CTime &t){    return ((*this<t)||(*this>t));}//可以直接使用已经重载了的加减运算实现//这种赋值, 例如 t1+=20，直接改变当前对象的值，所以在运算完成后，将*this作为返回值CTime CTime::operator+(CTime &t){    int h,m,s;    s=second+t.second;    m=minute+t.minute;    h=hour+t.hour;    if(s>59)    {        m++;        s-=60;    }    if(m>59)    {        h++;        m-=60;    }    if(h>23)        h-=24;    CTime t1(h,m,s);    return t1;}CTime CTime::operator+(int s){    int ss=s%60;    int mm=(s/60)%60;    int hh=s/3600;    CTime t0(hh,mm,ss);    return *this+t0;}CTime CTime::operator-(CTime &t){    int s,m,h;    s=second-t.second;    m=minute-t.minute;    h=hour-t.hour;    if(s<0)    {        m--;        s+=60;    }    if(m<0)    {        h--;        m+=60;    }    if(h<0)        h+=24;    CTime t1(h,m,s);    return t1;}CTime CTime::operator-(int s){    int ss=s%60;    int mm=(s/60)%60;    int hh=s/3600;    CTime t0(hh,mm,ss);    return *this-t0;}CTime CTime::operator+=(CTime &c){    *this=*this+c;    return *this;}CTime CTime::operator-=(CTime &c){    *this=*this-c;    return *this;}CTime CTime::operator+=(int s)//返回s秒后的时间{    *this=*this+s;    return *this;}CTime CTime::operator-=(int s){    *this=*this-s;    return *this;}CTime CTime::operator++(int)//后置++，下一秒{    CTime t=*this;    *this=*this+1;    return t;}CTime CTime::operator++()//前置++，下一秒{    *this=*this+1;    return *this;}CTime CTime::operator--(int)//后置--，前一秒{    CTime t=*this;    *this=*this-1;    return t;}CTime CTime::operator--()//前置--，前一秒{    *this=*this-1;    return *this;}int main(){    CTime t1,t2,t;    cout<<"t1为：";    cin>>t1;    cout<<"t2为：";    cin>>t2;    cout<<"下面比较两个时间大小：\n";    if (t1>t2) cout<<"t1>t2"<<endl;    if (t1<t2) cout<<"t1<t2"<<endl;    if (t1==t2) cout<<"t1＝t2"<<endl;    if (t1!=t2) cout<<"t1≠t2"<<endl;    if (t1>=t2) cout<<"t1≥t2"<<endl;    if (t1<=t2) cout<<"t1≤t2"<<endl;    cout<<endl;    cout<<"t1= "<<t1<<endl;    cout<<"t2= "<<t2<<endl;    cout<<"t=t1++"<<endl;    t=t1++;    cout<<"t= "<<t<<"    t1= "<<t1<<endl;    cout<<"t=++t1"<<endl;    t=++t1;    cout<<"t= "<<t<<"    t1= "<<t1<<endl;    cout<<"t1+t2= "<<t1+t2<<endl;    cout<<"t1-t2= "<<t1-t2<<endl;    cout<<"t1+20= "<<t1+20<<endl;    cout<<"t1-50= "<<t1-50<<endl;    return 0;}