atlmap.cpp

#include "stdafx.h"
#include <vector>
#include <stdio.h>
#include <atlcoll.h>

int _tmain(int argc, _TCHAR* argv[])
{
    std::vector<int> data;
    data.resize(10000000);
    FILE *f = fopen("ints.dat", "rb");
    if (!f) {
        printf("can't open file");
        return 1;
    }
    auto sz = fread(&data[0], 4, 10000000, f);
    printf("sz=%d\n", sz);
    fclose(f);

    LARGE_INTEGER t0, t1, t2, fr;	
    CAtlMap<int, int> h;
    QueryPerformanceCounter(&t0);
    for(int i=0; i<data.size(); i++) {
        int x = data[i];
        auto pair = h.Lookup(x);
        if (pair==NULL)
            h[x] = 1;
        else
            pair->m_value++;
        //h[data[i]]++;
    }
    QueryPerformanceCounter(&t1);
    int v = 0;
    for(int i=0; i<data.size(); i++)
        v ^= h[data[i]];
    QueryPerformanceCounter(&t2);
    QueryPerformanceFrequency(&fr);
    double dt1 = (double)(t1.QuadPart - t0.QuadPart) / fr.QuadPart;
    double dt2 = (double)(t2.QuadPart - t1.QuadPart) / fr.QuadPart;
    printf("v=%d make=%lf read=%lf\n", v, dt1, dt2);
    for(int i=0;i<4;i++) 
        printf("%d %d\n", data[i], h[data[i]]);
    return 0;
}