combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:32:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
32 | if (ans == s.size()) s += letters[2];
| ~~~~^~~~~~~~~~~
combo.cpp:33:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
33 | else if (ans == s.size()+1) s += letters[1];
| ~~~~^~~~~~~~~~~~~
combo.cpp:37:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
37 | if (press(s+letters[0]) > s.size()) s += letters[0];
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~
combo.cpp:38:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
38 | else if (press(s+letters[1]) > s.size()) s+= letters[1];
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~