1 void showTime() const;
2 Clock& operator ++();
3 Clock operator ++(int);
4 private:
5 int hour,minute,second;
6 };
7 Clock::Clock(int hour,int minute,int second){
8 if(0<=hour&&hour<24&&0<=minute&&minute<60&&0<=second&&second<60)
9 {
10 this->hour=hour;
11 this->minute=minute;
12 this->second=second;
13 }
14 else
15 cout<<"Time error!"<<endl;
16 }
17
18 void Clock::showTime() const
19 {
20 cout<<hour<<":"<<minute<<":"<<second<<endl;
21 }
22
23 Clock& Clock::operator ++()
24 {
25 second++;
26 if(second>=60)
27 {
28 second-=60;
29 minute++;
30 if(minute>=60)
31 {
32 minute-=60;
33 hour=(hour+1)%24;
34 }
35 return *this;
36 }
37 }
38
39 Clock Clock::operator ++(int)
40 {
41 Clock old=*this;
42 ++(*this);
43 return old;
44 }
45
46 int main()
47 {
48 Clock myClock(23,59,59);
49 cout<<"First time output:";
50 myClock.showTime();
51 cout<<"Show myClock++: ";
52 (myClock++).showTime();
53 cout<<"Show ++myClock: ";
54 (++myClock);
55 myClock.showTime();
56 return 0;
57 }
