combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:16:23: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
16 | while (ans.size() < N - 1) {
| ~~~~~~~~~~~^~~~~~~
combo.cpp:19:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
19 | if (ret == ans.size()) {
| ~~~~^~~~~~~~~~~~~
combo.cpp:21:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
21 | } else if (ret == ans.size() + 1) {
| ~~~~^~~~~~~~~~~~~~~~~
combo.cpp:27:20: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
27 | if (ans.size() == N) return ans;
| ~~~~~~~~~~~^~~~