Compilare: user.cpp: In function ‘void append(int, int)’: user.cpp:13:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<l[lista].size();j++) ^ user.cpp: In function ‘void dfs(int)’: user.cpp:30:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x].size();i++) ^