#include <iostream>
using namespace std;
class Time
{
public:
Time(int m=0,int n=0,int s=0);
void show_time( ); //根据is_24和from0,输出适合形式-20:23:5/8:23:5 pm/08:23:05 pm
void add_seconds(int); //增加n秒钟
void add_minutes(int); //增加n分钟
void add_hours(int); //增加n小时
static void change24(); //改变静态成员is_24,在12和24时制之间转换
static void changefrom0(); //改变静态成员from0,切换是否前导0
private:
static bool is_24; //为true时,24小时制,如20:23:5;为flase,12小时制,显示为8:23:5 pm
static bool from0; //为true时,前导0,8:23:5显示为08:23:05
int hour;
int minute;
int sec;
};
//下面写出静态成员的初始化及各成员函数的定义
bool Time::is_24=true; //为true时,24小时制,如20:23:5;为flase,12小时制,显示为8:23:5 pm
bool Time::from0=false; //为true时,前导0,8:23:5显示为08:23:05
Time::Time(int h,int m,int s)
{
hour=h;
minute=m;
sec=s;
}
void Time::show_time( ) //根据is_24和from0,输出适合形式-20:23:5/8:23:5 pm/08:23:05 pm
{
int h;
if(is_24)
h=hour;
else
h=hour%12;
if(hour<10&&from0)
cout<<'0'<<h<<':';
else cout<<h<<':';
if(minute<10&&from0)
cout<<'0'<<minute<<':';
else cout<<minute<<':';
if(sec<10&&from0)
cout<<sec;
if(!is_24)
{
if(hour>12)
cout<<" PM";
else
cout<<" AM";
}
cout<<endl;
}
void Time::add_seconds(int n) //增加n秒钟
{
sec+=n;
if(sec>59)
{
add_minutes(sec/60);
sec%=60;
}
}
void Time::add_minutes(int n) //增加n分钟
{
minute+=n;
if(minute>59)
{
add_hours(minute/60);
minute%=60;
}
}
void Time::add_hours(int n) //增加n小时
{
hour+=n;
if(hour>23)
{
hour%=24;
}
}
void Time::change24() //改变静态成员is_24,在12和24时制之间转换
{
is_24=!is_24;
}
void Time::changefrom0() //改变静态成员from0,切换是否前导0
{
from0=!from0;
}
int main()
{
Time t1(23,14,25),t2(8,45,6);
cout<<"24时制, 不前导:"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
t1.add_hours(10);
t2.add_hours(10);
Time::changefrom0(); //注意此处调用静态成员
cout<<"10小时后, 切换为前导:"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
t1.change24();
cout<<"换一种制式(12):"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
return 0;
}

#include <iostream>
using namespace std;
class Time
{
public:
Time(int m=0,int n=0,int s=0);
void show_time( ); //根据is_24和from0,输出适合形式-20:23:5/8:23:5 pm/08:23:05 pm
void add_seconds(int); //增加n秒钟
void add_minutes(int); //增加n分钟
void add_hours(int); //增加n小时
static void change24(); //改变静态成员is_24,在12和24时制之间转换
static void changefrom0(); //改变静态成员from0,切换是否前导0
private:
static bool is_24; //为true时,24小时制,如20:23:5;为flase,12小时制,显示为8:23:5 pm
static bool from0; //为true时,前导0,8:23:5显示为08:23:05
int hour;
int minute;
int sec;
};
//下面写出静态成员的初始化及各成员函数的定义
bool Time::is_24=true; //为true时,24小时制,如20:23:5;为flase,12小时制,显示为8:23:5 pm
bool Time::from0=false; //为true时,前导0,8:23:5显示为08:23:05
Time::Time(int h,int m,int s)
{
hour=h;
minute=m;
sec=s;
}
void Time::show_time( ) //根据is_24和from0,输出适合形式-20:23:5/8:23:5 pm/08:23:05 pm
{
int h;
if(is_24)
h=hour;
else
h=hour%12;
if(hour<10&&from0)
cout<<'0'<<h<<':';
else cout<<h<<':';
if(minute<10&&from0)
cout<<'0'<<minute<<':';
else cout<<minute<<':';
if(sec<10&&from0)
cout<<sec;
if(!is_24)
{
if(hour>12)
cout<<" PM";
else
cout<<" AM";
}
cout<<endl;
}
void Time::add_seconds(int n) //增加n秒钟
{
sec+=n;
if(sec>59)
{
add_minutes(sec/60);
sec%=60;
}
}
void Time::add_minutes(int n) //增加n分钟
{
minute+=n;
if(minute>59)
{
add_hours(minute/60);
minute%=60;
}
}
void Time::add_hours(int n) //增加n小时
{
hour+=n;
if(hour>23)
{
hour%=24;
}
}
void Time::change24() //改变静态成员is_24,在12和24时制之间转换
{
is_24=!is_24;
}
void Time::changefrom0() //改变静态成员from0,切换是否前导0
{
from0=!from0;
}
int main()
{
Time t1(23,14,25),t2(8,45,6);
cout<<"24时制, 不前导:"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
t1.add_hours(10);
t2.add_hours(10);
Time::changefrom0(); //注意此处调用静态成员
cout<<"10小时后, 切换为前导:"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
t1.change24();
cout<<"换一种制式(12):"<<endl;
cout<<"t1是:";
t1.show_time();
cout<<"t2是:";
t2.show_time();
return 0;
}