c加加自定义类型名小写错误不知道为啥QAQ

Question

#include
#include
#include<windows.h>
#include
using namespace std;
class Clock
{
public:
void setTime(int newH, int newM, int newS);
void run();
void showTime();
private:
int hour, minute, second;
};
void Clock::setTime(int newH, int newM, int newS)
{
hour = newH;
minute = newM;
second = newS;
}
void Clock::showTime()
{
if (hour > 24 && minute > 60 && second > 60)
cout << "输入的值有问题" << endl;
else
cout << hour << ';' << minute << ';' << second << ';' << endl;
}
void Clock::run()
{
while (1)
{
second += 1;
if (second >= 60)
{
second -= 60;
minute = minute + 1;
}
if (minute >= 60)
{
minute -= 60;
hour += 1;
}
if (hour >= 24)
{
hour -= 24;
}
system("cls");
showTime();
Sleep(1000);
}
}
int main()
{
Clock myclock; //这里假如改成clock 会报错
myclock.setTime(0, 0, 0);
myclock.showTime();
myclock.run();
return 0;
} //上面的程序是对的，但是假如我把Clock 改成小写clock，系统就会报错说未定义标识符clock，但是加个class又行。不太懂

Answer 1

clock是系统函数
clock
Calculates the processor time used by the calling process.

clock_t clock( void );

Routine Required Header Compatibility
clock <time.h>