Compilare: main.cpp: In function 'int main()': main.cpp:84:8: warning: variable 'has_cycle' set but not used [-Wunused-but-set-variable] auto has_cycle = [&]() { ^~~~~~~~~ main.cpp:105:7: warning: unused variable 'iters' [-Wunused-variable] int iters = 0; ^~~~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:15:32: 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); ^