Compilare: user.cpp: In function ‘void erase(int)’: user.cpp:117:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < h[b].size(); ++ i) ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:13:35: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, SIZE, in); ^