Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:15:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<l[nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:27:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<l[x].size();j++) ^ user.cpp:38:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<z.size();i++) ^