Compilare: main.cpp: In function 'std::pair<long long int, int> check(long long int)': main.cpp:115:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<burn.size();i++){ ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:157:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("popcorn.in","r",stdin); ^ main.cpp:158:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("popcorn.out","w",stdout); ^