第九周实验报告（任务二）【Time类中《和》运算符的重载】

#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);//构造函数的声明
void setTime(int h,int m,int s);
friend ostream& operator << (ostream&,CTime&);//声明流插入运算符"<<"的重载
friend istream& operator >> (istream&,CTime&);//声明流插入运算符">>"的重载
//比较运算符(二目)的重载
bool operator > (CTime &t);
bool operator < (CTime &t);
bool operator >= (CTime &t);
bool operator <= (CTime &t);
bool operator == (CTime &t);
bool operator != (CTime &t);
//二目运算符的重载
CTime operator+(CTime &c);//返回c所规定的时、分、秒后的时间，例t1(8,20,25),t2(11,20,50)，t1+t2为:41:15
CTime operator-(CTime &c);//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
//一目运算符的重载
CTime operator++(int);//后置++，下一秒
CTime operator++();//前置++，下一秒
CTime operator--(int);//后置--，前一秒
CTime operator--();//前置--，前一秒
//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
};
//下面实现所有的运算符重载代码。为简化编程，请注意通过调用已有函数，利用好各函数之间的关系

//构造函数的定义
CTime::CTime(int h,int m,int s):hour(h),minute(m),second(s){}

//实现setTime函数
void CTime::setTime(int h,int m,int s)
{
hour=h;
minute=m;
second=s;
}

//比较运算符(二目)的重载
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)
{
if(*this<t) return false;
return  true;
}

bool CTime::operator <= (CTime &t)
{
if(*this>t) return false;
return  true;
}

bool CTime::operator == (CTime &t)
{
if(*this<t||*this>t) return false;
return   true;
}

bool CTime::operator != (CTime &t)
{
if(*this==t) return false;
return  true;
}

//二目运算符的重载
//返回c所规定的时、分、秒后的时间，例t1(8,20,25),t2(11,20,50)，t1+t2为:41:15
CTime CTime::operator+(CTime &c)
{
int h,m,s;
s=second+c.second;
m=minute+c.minute;
h=hour+c.hour;
if(second>59)
{
second-=60;
minute+=1;
}
if(minute>59)
{
minute-=60;
hour+=1;
}
while(h>23) h-=24;
CTime t0(h,m,s);
return t0;
}

//对照+理解
CTime CTime::operator-(CTime &c)
{
int h,m,s;
s=second-c.second;
m=minute-c.minute;
h=hour-c.hour;
if(second<0)
{
second+=60;
minute-=1;
}
if(minute<0)
{
minute+=60;
hour-=1;
}
while(h<0) h+=24;
CTime t0(h,m,s);
return t0;
}
//返回s秒后的时间
CTime CTime::operator+(int s)
{
int ss=s%60;
int mm=(s/60)%60;
int hh=s/3600;
CTime t0(hh,mm,ss);
return t0;
}

//返回s秒前的时间
CTime CTime::operator-(int s)
{
int ss=s%60;
int mm=(s/60)%60;
int hh=s/3600;
CTime t0(hh,mm,ss);
return t0;
}

//一目运算符的重载
//后置++，下一秒
CTime CTime::operator++(int)
{
CTime t=*this;
*this=*this+1;
return t;
}

//前置++，下一秒
CTime CTime::operator++()
{
*this=*this+1;
return *this;
}

//后置--，前一秒
CTime CTime::operator--(int)
{
CTime t=*this;
*this=*this-1;
return t;
}

//前置--，前一秒
CTime CTime::operator--()
{
*this=*this-1;
return *this;
}

//赋值运算符的重载
CTime CTime::operator+=(CTime &c)
{
*this+=c;
return *this;
}

CTime CTime::operator-=(CTime &c)
{
*this-=c;
return *this;
}

//返回s秒后的时间
CTime CTime::operator+=(int s)
{
*this+=s;
return *this;
}

//返回s秒前的时间
CTime CTime::operator-=(int s)
{
*this-=s;
return *this;
}

//声明流插入运算符"<<"的重载
ostream& operator << (ostream& output,CTime& c)
{
output<<c.hour<<":"<<c.minute<<":"<<c.second;
return output;
}

//声明流插入运算符">>"的重载
istream& operator >> (istream& input ,CTime& c)
{
cout<<"Please input time: ";
input>>c.hour>>c.minute>>c.second;
return input;
}

void main()
{
CTime t1,t2,t;
cin>>t1;
cout<<"t1为："<<t1<<endl;
cin>>t2;
cout<<"t2为："<<t2<<endl;
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;
//下面自行设计对其他运算符的重载的测试
t=t1+t2;
cout<<"t1+t2="<<t<<endl;
t=t1-t2;
cout<<"t1-t2="<<t<<endl;
t=t1+20;
cout<<"t1+20="<<t<<endl;
t=t1-10;
cout<<"t1-10="<<t<<endl;
t=t1++;
cout<<"t1++="<<t<<endl;
t=++t1;
cout<<"++t1="<<t<<endl;
t=t1--;
cout<<"t1--="<<t<<endl;
t=--t1;
cout<<"--t1="<<t<<endl;
t1+=t2;
cout<<"t1+=t2="<<t<<endl;
t1-=t2;
cout<<"t1-=t2="<<t<<endl;
t1+=2000;
cout<<"t1+=2000="<<t<<endl;
t1-=2000;
cout<<"t1-=2000"<<t<<endl;
}