combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:11:23: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
11 | while (s.length() < N)
| ~~~~~~~~~~~^~~
combo.cpp:21:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
21 | if (n > s.length())
| ~~^~~~~~~~~~~~