第九周任务2

#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);

//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
friend ostream& operator << (ostream&,CTime&);
friend istream& operator << (istream&,CTime&);
};
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;
}

ostream& operator << (ostream& output,CTime& t)
{
output<<t.hour<<":"<<t.minute<<":"<<t.second<<endl;
return output;
}

istream& operator << (istream& input,int &n)
{
input>>n;
return input;
}

bool CTime::operator > (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n>0)
{
return true;
}
else
{
return false;
}
}

bool CTime::operator < (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n<0)
{
return true;
}
else
{
return false;
}
}

bool CTime::operator >= (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n>=0)
{
return true;
}
else
{
return false;
}
}

bool CTime::operator <= (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n<=0)
{
return true;
}
else
{
return false;
}
}

bool CTime::operator == (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n==0)
{
return true;
}
else
{
return false;
}
}
bool CTime::operator != (CTime &t)
{
int n;
n=(hour*3600+minute*60+second)-(t.hour*3600+t.minute*60+t.second);
if(n==0)
{
return false;
}
else
{
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 &t)
{

int h,m,s;
s=second+t.second;
m=minute+t.minute;
h=hour+t.hour;
if (s>59)
{
s-=60;
m++;
}
if (m>59)
{
m-=60;
h++;
}
while (h>23) h-=24;
CTime t0(h,m,s);
return t0;
}

//对照+理解
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--;
}
if (h<0) h+=24;
CTime t0(h,m,s);
return t0;
}

//返回s秒后的时间
CTime CTime::operator+(int s)//返回s秒后的时间
{
CTime t;

t.hour =hour;
t.minute =minute ;
t.second =second ;
t.second =(t.second +s);
if (t.second >59)      //思考：if中的两条语句能否交换顺序？为什么不能？后果将是……？
{
t.minute+=t.second/60;    //增加sec/60分钟
if (t.minute>59)
{
t.hour+=t.minute/60;
if (t.hour>23)
t.hour%=24;
t.minute%=60;
}
t.second%=60;                //秒数应该是sec%=60
}
else if (t.minute>59)
{
t.hour+=t.minute/60;
if (t.hour>23)
t.hour%=24;
t.minute%=60;
}
else  if (t.hour>23)
t.hour%=24;
return t;
}

//返回s秒前的时间
CTime CTime::operator-(int s)
{
int time = hour * 3600 + minute * 60 + second;

time = time - s;

hour = time / 3600;

time = time % 3600;

minute = time / 60;

time = time % 60;

second = time;

return (*this);

}

//一目运算符的重载

//后置++，下一秒
CTime CTime::operator++(int)
{
CTime temp(* this);
second++;
if(second>59)
{
second -= 60;
++minute;
}
return temp;
}

//前置++，下一秒
CTime CTime::operator++()
{
if(++second>59)
{
second -= 60;
++minute;
}
return * this;
}

//后置--，前一秒
CTime CTime::operator--(int)
{
CTime temp(* this);
second--;
if(second<0)
{
second += 60;
--minute;
}
return temp;
}

//前置--，前一秒
CTime CTime::operator--()
{
if(--second<0)
{
second += 60;
--minute;
}
return *this;
}

//赋值运算符的重载
CTime CTime::operator+=(CTime &c)
{
CTime t1,t;
t1.hour =hour;
t1.minute =minute ;
t1.second =second ;
t=t1+c;
hour=t.hour ;
minute=t.minute ;
second=t.second ;
return t;
}
CTime CTime::operator-=(CTime &c)
{
CTime t1,t;
t1.hour =hour;
t1.minute =minute ;
t1.second =second ;
t=t1-c;
hour=t.hour ;
minute=t.minute ;
second=t.second ;
return t;

}
//返回s秒后的时间
CTime CTime::operator+=(int s)
{
CTime t1,t;
t1.hour =hour;
t1.minute =minute ;
t1.second =second ;
t=t1+s;
hour=t.hour ;
minute=t.minute ;
second=t.second ;
return t;
}
//返回s秒前的时间
CTime CTime::operator-=(int s)
{
CTime t1,t;
t1.hour =hour;
t1.minute =minute ;
t1.second =second ;
t=t1-s;
hour=t.hour ;
minute=t.minute ;
second=t.second ;
return t;
}
void main()
{
CTime t1(5,21,20),t2(13,14,52),t;
int n;
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<<"t1+t2的时间为：";
t=t1+t2;
cout<<t;
cout<<"t1-t2的时间为：";
t=t1-t2;
cout<<t;
cout<<endl;
cout<<"请输入您想增加的秒数：";
cin>>n;
t=t1+n;
cout<<"增加"<<n<<"秒后的时间为：";
cout<<t;
t=t1-n;
cout<<"增加"<<n<<"秒前的时间为：";
cout<<t;
cout<<endl;
cout<<"对t1后置++,结果为：";
t=t1++;
cout<<t;
cout<<"运算结束后，t1的值为：";
cout<<t1;
cout<<endl;
cout<<"对t1前置++,结果为：";
t=++t1;
cout<<t;
cout<<"运算结束后，t1的值为：";
cout<<t;
cout<<endl;
cout<<"对t1后置--,结果为：";
t=t1--;
cout<<t;
cout<<"运算结束后，t1的值为：";
cout<<t1;
cout<<endl;
cout<<"对t1前置--,结果为：";
t=--t1;
cout<<t;
cout<<"运算结束后，t1的值为：";
cout<<t1;
cout<<endl;
cout<<"运算t1+=t2的结果为：";
t1+=t2;
cout<<t1;
cout<<endl;
cout<<"此时t1的值为：";
cout<<t1;
cout<<"此时t2的值为：";
cout<<t2;
cout<<endl;
cout<<"运算t1-=t2的结果为：";
t1-=t2;
cout<<t1;
cout<<"此时t1的值为：";
cout<<t1;
cout<<"此时t2的值为：";
cout<<t2;
cout<<endl;
system("PAUSE");
}