第九周项目二——Time类中的运算符重载（续）

<img src="http://img.blog.csdn.net/20150513081909860?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvY2QxMjAy/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />/* *Copyright  (c)  2014,烟台大学计算机学院 *All rights reserved. *文件名称: test.cpp *作        者:陈丹 *完成日期:2015年5月13日 *版本号:v1.0 * *问题描述:在Time类中的运算符重载基础上（1）定义对时间对象的自增和自减一目运算符（2）定义Time类中的<<和>>运算符重载，实现时间的输入输出 *输入描述: *程序输出: */#include <iostream>#include <iomanip>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):hour(h),minute(m),second(s) {};    void setTime(int h,int m,int s);    friend ostream& operator << (ostream&output,const CTime &c);    //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    //一目运算符的重载    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};void CTime::setTime(int h,int m,int s){    hour=h;    minute=m;    second=s;}ostream& operator << (ostream&output,const CTime &c){    output<<setw(2)<<setfill('0')<<c.hour<<":";    output<<setw(2)<<setfill('0')<<c.minute<<":";    output<<setw(2)<<setfill('0')<<c.second;    return output;}bool CTime::operator > (CTime &t){    int t1,t2;    t1=hour*3600+minute*60+second;    t2=t.hour*3600+t.minute*60+t.second;    if(t1>t2)        return true;    else        return false;}bool CTime::operator < (CTime &t){    int t1,t2;    t1=hour*3600+minute*60+second;    t2=t.hour*3600+t.minute*60+t.second;    if(t1<t2)        return true;    else        return false;}bool CTime::operator <= (CTime &t){    return !(*this>t);}bool CTime::operator >= (CTime &t){    return !(*this<t);}bool CTime::operator == (CTime &t){    if(hour==t.hour&&minute==t.minute&&second==t.second)        return true;    else        return false;}bool CTime::operator != (CTime &t){    return !(*this==t);}CTime CTime::operator + (CTime &t){    CTime t1;    t1.second=second+t.second;    t1.minute=minute+t.minute;    t1.hour=hour+t.hour;    if(t1.second>59)    {        t1.second%=60;        t1.minute++;    }    if(t1.minute>59)    {        t1.minute%=60;        t1.hour++;    }    if(t1.hour>23)    {        hour%=24;    }    return t1;}CTime CTime::operator - (CTime &t){    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--;    }    while (h<0) h+=24;    CTime t0(h,m,s);    return t0;}CTime CTime::operator+(int s){    CTime t1(0,0,s);    return *this+t1;}CTime CTime::operator-(int s){    CTime t1(0,0,s);    return *this-t1;}//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 &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{    int ss=s%60;    int mm=(s/60)%60;    int hh=s/3600;    CTime t0(hh,mm,ss);    *this=*this+t0;    return *this;}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),t;    *this=*this-t0;    return *this;}//下面定义用于测试的main()函数//一目运算符的重载CTime CTime::operator++(int)//后置++，下一秒{    CTime c=*this;    *this+=1;    return c;}CTime CTime::operator++()//前置++，下一秒，前置与后置返回值不一样{    *this+=1;    return *this;}CTime CTime::operator--( int)//后置--，前一秒{    CTime c=*this;    *this-=1;    return c;}CTime CTime::operator--()//前置--，前一秒{    *this-=1;    return *this;}int main(){    CTime t1,t2,t3;    int s=20;    t1.setTime(8,20,25);    t2.setTime(11,20,50);    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<<t1<<"+"<<t2<<"="<<t1+t2<<endl;    cout<<t1<<"-"<<t2<<"="<<t1-t2<<endl;    cout<<t1<<"+"<<s<<"s"<<"=";    t3=t1+s;    cout<<t3<<endl;    cout<<t1<<"-"<<s<<"s"<<"=";    t3=t1-s;    cout<<t3<<endl;    cout<<t1<<"+="<<t2<<"=";    t1+=t2;    cout<<t1<<endl;    cout<<t1<<"-="<<t2<<"=";    t1-=t2;    cout<<t1<<endl;    cout<<t1<<"+="<<s<<"s"<<" = ";    t1+=s;    cout<<t1<<endl;    cout<<t1<<"-="<<s<<"s"<<" = ";    t1-=s;    cout<<t1<<endl;    cout<<t1<<"++ = ";    cout<<(t1++)<<endl;    cout<<"++"<<t1<<" = ";    cout<<(++t1)<<endl;    cout<<t2<<"-- = ";    cout<<(t2--)<<endl;    cout<<"--"<<t2<<" = ";    cout<<(--t2)<<endl;    return 0;}

运行结果：