67

#include <iostream>
#include <vector>
#include <cmath>
using namespace std;

int main()
{

    vector<char> prime(10000001, true);
    prime[0] = prime[1] = false;
    for (int i = 2; i <= 10000000; ++i)
        if (prime[i])
            if (i * 1ll * i <= 10000000)
                for (int j = i * i; j <= 10000000; j += i)
                    prime[j] = false;

    for (int i = 3000000; i < 10000000 - 1; ++i)
    {

        if (prime[i] && prime[i + 2])
        {
            cout << i << ' ' << i + 2 << '\n';
        }
    }
    return 0;
}