combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:18:14: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
18 | if(s.size()<N-1){
| ~~~~~~~~^~~~
combo.cpp:21:10: 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(ans==s.size()+2) s+=a[idx+1];
| ~~~^~~~~~~~~~~~
combo.cpp:22:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
22 | else if(ans==s.size()+1) s+=a[idx+2];
| ~~~^~~~~~~~~~~~
combo.cpp:28:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
28 | if(press(q)==s.size()+1){
| ~~~~~~~~^~~~~~~~~~~~
combo.cpp:30:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
30 | if(press(q2)==s.size()+1) s+=a[idx+1];
| ~~~~~~~~~^~~~~~~~~~~~