Time类中的运算符重载

#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);
    void display();
    //比较运算重载的函数定义
    bool operator > (CTime &t);
    bool operator < (CTime &t);
    bool operator >= (CTime &t);
    bool operator <= (CTime &t);
    bool operator == (CTime &t);
    bool operator != (CTime &t);
    //二目运算函数的定义
    CTime operator+(CTime &t);
    CTime operator-(CTime &t);
    CTime operator+(int s);//返回s秒后的时间
    CTime operator-(int s);//返回s秒前的时间
    //二目赋值运算符函数的定义
    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::CTime(int h,int m,int s)
{
    hour=h;
    minute=m;
    second=s;
}
void CTime::setTime(int h,int m,int s)
{
    hour=h;
    minute=m;
    second=s;
}
void CTime::display()
{
    cout<<hour<<":"<<minute<<":"<<second<<endl;
}

//比较运算符重载

bool CTime::operator > (CTime &t)
{
    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 ;
    if(second<t.second)return false;
}
bool CTime::operator < (CTime &t)
{
    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 ;
    if(second>t.second)return false;
}
bool CTime::operator >= (CTime &t)
{
    if(*this<t)return false ;
    else
        return  true;
}
bool CTime::operator <= (CTime &t)
{
    if(*this>t)return false;
    else
        return true;
}
bool CTime::operator == (CTime &t)
{
    if(*this>t||*this<t)
        return false;
    else
        return true;
}
bool CTime::operator != (CTime &t)
{
    if(*this==t)
        return false;
    else
        return true;
}
//二目运算符的重载
CTime CTime:: operator+(CTime &t)// 计算时间之和
{
    int h,m,s;
    s=second+t.second;
    m=minute+t.minute;
    h=hour+t.hour;
    if(s>59)
    {
        s%=60;
        m++;
    }
    if(m>60)
    {
        m%=60;
        h++;
    }
    if(h>23)
    {
        h-=24;
    }
    CTime t0(h,m,s);
    return t0;
}
CTime CTime::operator-(CTime &t)// 计算时间之差
{
    int h,m,s;
    s=second-t.second;
    m=minute-t.minute;
    h=hour-t.hour;
    if (s<0)
    {
        s+=60;
        m--;
    }
    if (m<0)
    {
        m+=60;
        h--;
    }
    if (h<0)
    {
        h+=24;
    }
    CTime t0(h,m,s);
    return t0;
}
CTime CTime:: operator+(int s)//返回s秒后的时间
{
    int ss=s%60;
    int mm=(s/60)%60;
    int hh=s/3600;
    CTime t0(hh,mm,ss);
    return *this-t0;
}
CTime CTime::operator-(int s)//返回s秒前的时间
{
    int ss=s%60;
    int mm=(s/60)%60;
    int hh=s/3600;
    CTime t0(hh,mm,ss);
    return *this-t0;
}
//可以直接使用已经重载了的加减运算实现
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)//返回s秒前的时间
{
    *this=*this-s;
    return *this;
}

int main()
{
    CTime t1(8,20,25),t2(11,20,50),t;
    cout<<"t1为：";
    t1.display();
    cout<<"t2为：";
    t2.display();
    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;
    t=t1+t2;
    t.display();
    t=t1-t2;
    t.display();
    t=t1+2000;
    t.display();
    t=t1-5000;
    t.display();
    t1+=t2;
    t1.display();
    t1-=t2;
    t1.display();
    t1+=2000;
    t1.display();
    t1-=5000;
    t1.display();
    return 0;
}