bool prime(int n) {
  for (int i = 2; i < n; ++i) {
    if (n % i == 0) {
      return false;
    }
  }
  return true;
}

class PrimeNumberGenerator {
 public:
  explicit PrimeNumberGenerator(int start) {
    number = start;
  }
  int GetNextPrime() {
    if (!flag) {
      flag = true;
      if (prime(number) && number != 1) {
        return number;
      }
    }
    ++number;
    while (!prime(number)) {
      ++number;
    }
    return number;
  }

 private:
  int number;
  bool flag = false;
};