Compilare: user.cpp: In function ‘bool cmp(str, str)’: user.cpp:36:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a.x.size();++i) ~^~~~~~~~~~~ user.cpp: In function ‘int cc(std::__cxx11::string, std::__cxx11::string)’: user.cpp:46:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a.size();++i) ~^~~~~~~~~ user.cpp: In function ‘bool cmp(str, str)’: user.cpp:39:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int cb(std::__cxx11::string)’: user.cpp:70:1: warning: control reaches end of non-void function [-Wreturn-type] } ^