第8周-项目2-Time类中的运算符重载（续）-++、--、>>、<<

问题及代码：

/*   *Copyright (c)2015,烟台大学计算机与控制工程学院   *All rights reserved.   *文件名称：CTime.cpp   *作    者：单昕昕   *完成日期：2015年5月5日   *版 本 号：v1.0   *问题描述：（1）定义对时间对象的自增和自减一目运算符一目运算符的重载  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  （2）定义Time类中的<<和>>运算符重载，实现时间的输入输出，改造原程序中对运算结果显示方式，使程序读起来更自然。*程序输入：两个时间。*程序输出：时间运算结果。*/ //Sample Input//10:41:30 6:42:23#include<iostream>#include<cmath>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();    //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 &c);    friend ostream& operator<<(ostream&output,const CTime &c);};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;}//二目的比较运算符重载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;    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;    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));}//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19:41:15CTime CTime::operator+(CTime &t){    CTime time;    time.hour=hour+t.hour;    time.minute=minute+t.minute;    time.second=second+t.second;    int count=0;    int i=time.second;    if(time.second>=60)    {        while(i>=60)        {            i%=60;            count=(time.second-i)/60;        }        time.minute+=count;        time.second=i;    }    int j=time.minute;    count=0;    if (time.minute>=60)    {        while(j>=60)        {            j%=60;            count=(time.minute-j)/60;        }        time.hour+=count;        time.minute=j;    }    int k=time.hour;    count=0;    if (time.hour>=24)    {        while(k>=24)        {            k%=24;            count=(time.hour-k)/24;        }        time.hour=k;    }    return time;}CTime CTime::operator-(CTime &t)//对照+理解{    CTime time;    if(hour>t.hour)    {        time.hour=hour-t.hour;        time.minute=minute-t.minute;        time.second=second-t.second;        if(time.second<0)        {            time.minute--;            time.second+=60;        }        if(time.minute<0)        {            time.hour--;            time.minute+=60;        }    }    else    {        time.hour=t.hour-hour;        time.minute=t.minute-minute;        time.second=t.second-second;        if(time.second<0)        {            time.minute--;            time.second+=60;        }        if(time.minute<0)        {            time.hour--;            time.minute+=60;        }    }    return time;}CTime CTime::operator+(int s)//返回s秒后的时间{    CTime time;    second+=s;    int count=0;    int i=second;    if(second>=60)    {        while(i>=60)        {            i%=60;            count=(second-i)/60;        }        minute+=count;        second=i;    }    int j=minute;    count=0;    if (minute>=60)    {        while(j>=60)        {            j%=60;            count=(minute-j)/60;        }        hour+=count;        minute=j;    }    int k=hour;    count=0;    if (hour>=24)    {        while(k>=24)        {            k%=24;            count=(hour-k)/24;        }        hour=k;    }    time.hour=hour;    time.minute=minute;    time.second=second;    return time;}CTime CTime::operator-(int s)//返回s秒前的时间{    CTime time;    second-=s;    int count=0;    int i=fabs(second);    if(second>=60)    {        while(i>=60)        {            i%=60;            count=(second-i)/60;        }        minute-=count;        second=i;    }    int j=minute;    count=0;    if (minute>=60)    {        while(j>=60)        {            j%=60;            count=(minute-j)/60;        }        hour-=count;        minute=j;    }    int k=hour;    count=0;    if (hour>=24)    {        while(k>=24)        {            k%=24;            count=(hour-k)/24;        }        hour=k;    }    time.hour=hour;    time.minute=minute;    time.second=second;    return time;}//二目赋值运算符的重载CTime CTime::operator+=(CTime &c){    this->hour=this->hour+c.hour;    this->minute=this->minute+c.minute;    this->second=this->second+c.second;    int count=0;    int i=this->second;    if(this->second>=60)    {        while(i>=60)        {            i%=60;            count=(this->second-i)/60;        }        this->minute+=count;        this->second=i;    }    int j=this->minute;    count=0;    if (this->minute>=60)    {        while(j>=60)        {            j%=60;            count=(this->minute-j)/60;        }        this->hour+=count;        this->minute=j;    }    int k=this->hour;    count=0;    if (this->hour>=24)    {        while(k>=24)        {            k%=24;            count=(this->hour-k)/24;        }        this->hour=k;    }    return *this;}CTime CTime::operator-=(CTime &c){    if(this->hour>c.hour)    {        this->hour=this->hour-c.hour;        this->minute=this->minute-c.minute;        this->second=this->second-c.second;        if(this->second<0)        {            this->minute--;            this->second+=60;        }        if(this->minute<0)        {            this->hour--;            this->minute+=60;        }    }    else    {        this->hour=c.hour-this->hour;        this->minute=this->minute-c.minute;        this->second=this->second-c.second;        if(this->second<0)        {            this->minute--;            this->second+=60;        }        if(this->minute<0)        {            this->hour--;            this->minute+=60;        }    }    return *this;}CTime CTime::operator+=(int s)//返回s秒后的时间{    this->second+=s;    int count=0;    int i=this->second;    if(this->second>=60)    {        while(i>=60)        {            i%=60;            count=(this->second-i)/60;        }        this->minute+=count;        this->second=i;    }    int j=this->minute;    count=0;    if (this->minute>=60)    {        while(j>=60)        {            j%=60;            count=(this->minute-j)/60;        }        this->hour+=count;        this->minute=j;    }    int k=this->hour;    count=0;    if (this->hour>=24)    {        while(k>=24)        {            k%=24;            count=(this->hour-k)/24;        }        this->hour=k;    }    this->hour=hour;    this->minute=minute;    this->second=second;    return *this;}CTime CTime::operator-=(int s)//返回s秒前的时间{    this->second-=s;    int count=0;    int i=fabs(this->second);    if(this->second>=60)    {        while(i>=60)        {            i%=60;            count=(this->second-i)/60;        }        this->minute-=count;        this->second=i;    }    int j=this->minute;    count=0;    if (this->minute>=60)    {        while(j>=60)        {            j%=60;            count=(this->minute-j)/60;        }        this->hour-=count;        this->minute=j;    }    int k=this->hour;    count=0;    if (this->hour>=24)    {        while(k>=24)        {            k%=24;            count=(this->hour-k)/24;        }        this->hour=k;    }    this->hour=hour;    this->minute=minute;    this->second=second;    return *this;}CTime CTime::operator++(int)//后置++，下一秒{    CTime temp(*this);    second++;    if(second>=60)    {        second-=60;        ++minute;    }    return temp;}CTime CTime::operator++()//前置++，下一秒，前置与后置返回值不一样{    if(++second>=60)    {        second-=60;        ++minute;    }    return *this;}CTime CTime::operator--( int)//后置--，前一秒{    CTime temp(*this);    second--;    if(second<0)    {        second+=60;        --minute;    }    return temp;}CTime CTime::operator--()//前置--，前一秒{    if(--second<0)    {        second+=60;        --minute;    }    return *this;}//流插入istream& operator>>(istream&input,CTime &t){    int h,m,s;    char sign;    do    {        cout<<"please input a time(ep->h:m:s)：";        input>>h>>sign>>m>>sign>>s;    }    while(!(sign==':'));    t.hour=h;    t.minute=m;    t.second=s;    return input;}//流提取ostream& operator<<(ostream&output,const CTime &t){    output<<t.hour<<":"<<t.minute<<":"<<t.second<<endl;    return output;}//下面定义用于测试的main()函数int main(){    CTime t1(10,41,30),t2(6,42,23),t;    cout<<"t1为："<<t1;    cout<<"t2为："<<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<<"下面对两个时间进行计算："<<endl;    t1++;    cout<<"t1++："<<t1;    ++t2;    cout<<"++t2："<<t2;    t1--;    cout<<"t1--："<<t1;    --t2;    cout<<"--t2："<<t2;    t=t1+t2;    cout<<"t1+t2："<<t;    t=t1-t2;    cout<<"t1-t2："<<t;    t=t1+333;    cout<<"t1+333s："<<t;    t=t2-2222;    cout<<"t2-2222s："<<t;    t1+=t2;    cout<<"t1+=t2："<<t1;    t1-=t2;    cout<<"t1-=t2："<<t1;    t1+=3333;    cout<<"t1+=3333s："<<t1;    t2-=222;    cout<<"t2-=222s："<<t2;}

运行结果：

知识点总结：

重载单目运算符。

学习心得：

一开始看我自己的程序很奇怪为什么t1--木有变化，找了好久都找不出来bug，后来才发现我先t1++了，所以再--后又变成原来的数值。