#include #include using namespace std; vector getPrimes(int n) { if (n <= 1) return vector(); vector prime(n + 1, true); prime[0] = prime[1] = false; vector primes; for (int i = 2; i * i <= n; i++) if (prime[i]) { for (int j = i * i; j <= n; j += i) prime[j] = false; primes.push_back(i); } return primes; } bool isPrime(long long n) { if (n <= 1) return false; for (long long i = 2; i * i <= n; i++) if (n % i == 0) return false; return true; } int main() { int n = 31; vector primes = getPrimes(n); for (int i = 0; i < primes.size(); i++) cout << primes[i] << " "; cout << endl; for (int i = 0; i <= n; i++) if (isPrime(i)) cout << i << " "; }