Compilare: main.cpp: In function 'int main()': main.cpp:31:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(it->second.size()>maxx) ~~~~~~~~~~~~~~~~~^~~~~ main.cpp:36:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] }else if(maxx == it->second.size())apmaxx++; ~~~~~^~~~~~~~~~~~~~~~~~~~ main.cpp:27:46: warning: variable 'itr' set but not used [-Wunused-but-set-variable] map < string, vector<string> >::iterator itr = Pluton.begin(); ^~~