Timer in CPP

Timer.cpp

#include"windows.h"
#include<string>
#include<vector>
#include<algorithm>
using namespace std;
LARGE_INTEGER Frequency, PerformanceCount1, PerformanceCount2;
void TimeStart(){
    QueryPerformanceCounter(&PerformanceCount1);
}
void TimeEnd(){
    QueryPerformanceCounter(&PerformanceCount2);
    float tdiff = static_cast<float>((
        ((PerformanceCount2.QuadPart - PerformanceCount1.QuadPart) * 1000) / Frequency.QuadPart));
    printf("%f seconds\n", tdiff / 1000);
}

const int loopCount = 10000;
const int vectorCount = 100;

int _tmain(int argc, TCHAR* argv[])
{
    QueryPerformanceFrequency(&Frequency);
    TimeStart();
    for (int loop = 0; loop<loopCount; ++loop)
    {
        vector<string> vs;
        for (size_t i = 0; i<vectorCount; ++i)
            vs.push_back("abc" + i);
    }
    TimeEnd();
    return 0;
}