combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:8:17: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
8 | while(s.size() < N) {
| ~~~~~~~~~^~~
combo.cpp:10:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
10 | if(x == s.size()+1) s += c[k];
| ~~^~~~~~~~~~~~~
combo.cpp:11:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
11 | else if (x == s.size()) s += c[k+2];
| ~~^~~~~~~~~~~