C语言计时精确到微秒demo

#include <stdio.h>
#include<Windows.h>

int main()
{
    LARGE_INTEGER m_liPerfFreq = { 0 };
    QueryPerformanceFrequency(&m_liPerfFreq);//常数，机器每秒滴答数1000000
    
    LARGE_INTEGER m_liPerfStart = { 0 };//开始计时所需变量
    LARGE_INTEGER liPerfNow = { 0 };//结束计时所需变量


    QueryPerformanceCounter(&m_liPerfStart);
    //计时区间起点
    for (int i = 0; i < 1000000; i++);
    //计时区间终点
    QueryPerformanceCounter(&liPerfNow);
    
    printf("计时区间占时%d微秒\n", 
    (((liPerfNow.QuadPart - m_liPerfStart.QuadPart) * 1000000) / m_liPerfFreq.QuadPart));
    
}
![在这里插入图片描述](https://img-blog.csdnimg.cn/080a09ee8578432cb419f11bcd963752.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5aWl5p6X5Yy55Lqa5a2m6Zmi,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center)