#include <iostream>
#include <time.h>
int main()
{
    const int N = 1000000;
    int* arr = new int[N + 1];

    double start = clock() * 1.0 / CLOCKS_PER_SEC;

    for (int i = 0; i <= N; i++)
    {
        arr[i] = 0;
    }


    for (int i = 1; i <= N; i++)
    {

        for (int j = i + i; j <= N; j += i)
            arr[j] += i;
    }
    for (int i = 1; i <= N; i++)
    {
        if (arr[i] <= N && arr[i] != i && arr[arr[i]] == i)
            std::cout << arr[i] << "  " << i << std::endl;

    }


    delete[]arr;

    double end = clock() * 1.0 / CLOCKS_PER_SEC;
    std::cout << end - start << "sec" << std::endl;

    return 0;

}