Compilare: user.cpp: In function ‘void Read_Out()’: user.cpp:29:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < D.size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:53:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.in" , "r", stdin); ^ user.cpp:54:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.out", "w", stdout); ^