vector<int> euler_sieve(int n) {
    vector<bool> is_composite(n + 1, false);
    vector<int> primes;

    for (int i = 2; i <= n; i++) {
        if (!is_composite[i])
            primes.push_back(i);

        for (int j = 0; __________________________ && (long long)i * primes[j] <= n; j++) {
            is_composite[i * primes[j]] = true;

            if (i % primes[j] == 0)
                break;
        }
    }
    return primes;
}