Compilare: main.cpp: In function 'int main()': main.cpp:38:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<Gr/gr && i<G[gr].size(); i++) ~^~~~~~~~~~~~~ main.cpp:46:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); i++) ~^~~~~~~~~