使用QueryPerformanceFrequency 计算程序执行时间

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#include <iostream>

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#include <windows.h>

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using

namespace

std;

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////////////////////////////////////////////////

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void

main()

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{

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_LARGE_INTEGER time_start;

/*开始时间*/

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_LARGE_INTEGER time_over;

/*结束时间*/

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double

dqFreq;

/*计时器频率*/

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LARGE_INTEGER f;

/*计时器频率*/

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QueryPerformanceFrequency(&f);

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dqFreq=(

double

)f.QuadPart;

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QueryPerformanceCounter(&time_start);

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Sleep(1000);

/*循环耗时*/

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QueryPerformanceCounter(&time_over);

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cout<<((time_over.QuadPart-time_start.QuadPart)/dqFreq)<<endl;

//单位为秒，精度为1000 000/（cpu主频）微秒

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}