Compilare: main.cpp: In instantiation of 'OutputParsing<F>& OutputParsing<F>::operator<<(F) [with F = int]': main.cpp:157:16: required from here main.cpp:83:9: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In member function 'void InputReader<T>::advance() [with T = int]': main.cpp:20:25: 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, input_file) ; ^~~~~ main.cpp: In constructor 'InputReader<T>::InputReader(const char*) [with T = int]': main.cpp:28:17: 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, input_file) ; ^~~~~