combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:40:17: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
40 | if(ans.size() != N-1)
| ~~~~~~~~~~~^~~~~~
combo.cpp:40:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
40 | if(ans.size() != N-1)
| ^~
combo.cpp:42:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
42 | for(int i=0; i<3; i++)
| ^~~
combo.cpp:8:18: warning: control reaches end of non-void function [-Wreturn-type]
8 | vector<char> v;
| ^