Compilare: user.cpp: In function ‘int main()’: user.cpp:65:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int t1=0;t1<v[i].first.size();t1++) ^ user.cpp:67:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(t<v[j].first.size() && v[j].first[t]!=v[i].first[t1]) ^ user.cpp:69:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(t==v[j].first.size()) ^