test running time of code fragment

gistfile1.cpp

LARGE_INTEGER BeginTime ;
LARGE_INTEGER EndTime ;
LARGE_INTEGER Frequency ;

QueryPerformanceFrequency(&Frequency);
QueryPerformanceCounter(&BeginTime) ;
//fragment to test
QueryPerformanceCounter(&EndTime) ;

cout.precision(10);
cout << "Begin: " <<(double)BeginTime.QuadPart <<std::endl;
cout << "End: " <<(double)EndTime.QuadPart <<std::endl;
cout << "Precision: " <<(1/(double)Frequency.QuadPart)*1000000<<"us"<<std::endl;
cout << "Time elapsed: " <<( ((EndTime.QuadPart - BeginTime.QuadPart)*1000000)/(double)Frequency.QuadPart)<<"us"<<std::endl;