Compilare: user.cpp: In function ‘int main()’: user.cpp:29:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[mul].size()-1; ++i) g<<v[mul][i]<<","; ^ user.cpp: In function ‘void eval()’: user.cpp:74:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<inter.size();++i) v[mul].push_back(inter[i]); ^ user.cpp:90:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<inter.size();++i) v[mul].push_back(inter[i]); ^ user.cpp:111:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<inter.size(); ++i) v[mul].push_back(inter[i]); ^