Compilare: main.cpp: In function 'void BFS(int)': main.cpp:26:13: warning: variable 'ok' set but not used [-Wunused-but-set-variable] 26 | int ok=0; | ^~ main.cpp:21:9: warning: unused variable 'd' [-Wunused-variable] 21 | int d[4]; | ^ main.cpp: In function 'int main()': main.cpp:72:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 72 | for(int i=0;i<s.size();i++) | ~^~~~~~~~~