Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:19:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < a[x].size() ; i++) ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:56:29: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] fout << rez<<" " << k <<'\n' ; ^~~~