windows系統中得到精確到微妙的時間

#include <windows.h>
#include <iostream>

  LARGE_INTEGER t1,t2,feq; 
  QueryPerformanceFrequency(&feq);//每秒跳動次數
  QueryPerformanceCounter(&t1);//測前跳動次數 
  for(int i = 0;i<10000;i++);
  QueryPerformanceCounter(&t2);//測后跳動次數
  double d=((double)t2.QuadPart-(double)t1.QuadPart)/((double)feq.QuadPart);//時間差秒
  std::cout<<d<<std::endl;