Compilare: user.cpp: In function ‘int main()’: user.cpp:133:34: warning: right operand of comma operator has no effect [-Wunused-value] P = St.top(), val; ^ user.cpp: In member function ‘void inputReader::advance()’: user.cpp:17:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread( buffer, SIZE, 1, inputFile ); ^ user.cpp: In constructor ‘inputReader::inputReader(const char*)’: user.cpp:29:44: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread( buffer, SIZE, 1, inputFile ); ^