c++实现精确计时 - c++编程基础

//获取比较准确是程序运行时间

#include
#include< windows.h>
using namespace std;

int main(void)
{

system("color F0");

cout.setf(ios::fixed);
cout.setf(ios::showpoint);
cout.precision(10);

//获取时钟频率
LARGE_INTEGER m_liPerfFreq={0};
QueryPerformanceFrequency(&m_liPerfFreq);

//获取初始计数
LARGE_INTEGER m_liPerfStart={0};
QueryPerformanceCounter(&m_liPerfStart);

//测试代码的位置
for(int ix=0;ix<100000;ix++){
cout<<" ";
}

//获取最后计数
LARGE_INTEGER liPerfNow={0};
QueryPerformanceCounter(&liPerfNow);

//计算时间

long long time=( ((liPerfNow.QuadPart - m_liPerfStart.QuadPart) * 1000)/m_liPerfFreq.QuadPart);

cout<

system("pause");
return 0;
}