Compilare: main.cpp: In member function 'char InParser::read_ch()': main.cpp:23:29: 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); ^ main.cpp: In function 'int main()': main.cpp:184:20: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized] fout << ans << '\n'; ^~~~