Compilare: main.cpp: In function 'int main()': main.cpp:17:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 17 | for (int i = 0; i < s.size(); ++i) | ~~^~~~~~~~~~ main.cpp:51:10: warning: variable 'comb' set but not used [-Wunused-but-set-variable] 51 | auto comb = [&](int n, int k) -> ull { | ^~~~