Compilare: user.cpp: In function ‘void generateAll(long long int, int, int, std::vector<int>&)’: user.cpp:21:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = index; i < primes.size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:42:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("porcjoc.out", "w", stdout); ^