Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:17:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<a[nod].size(); i++) ^ user.cpp: In function ‘void dfs2(int, bool*, int)’: user.cpp:25:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<a[nod].size(); i++) ^