Compilare: user.cpp: In function ‘int main()’: user.cpp:34:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(V[j] * V[j] <= nr && j < V.size()) ^ user.cpp:48:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i < V.size() && w; i++) ^ user.cpp:56:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i < V.size(); i++) ^