Compilare: user.cpp: In function ‘int main()’: user.cpp:130:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( j = 0; j < op[i].size(); j ++ ){ ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:17:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^