Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:23:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<V[v].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:77:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<D.size();j++) ^ user.cpp:96:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<R[i].size();j++) ^