Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:19:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i<G[x].size();i++) ^ user.cpp:21:24: warning: pointer to a function used in arithmetic [-Wpointer-arith] DFS[G[x][i]]; ^ user.cpp:21:24: warning: value computed is not used [-Wunused-value] user.cpp:21:24: warning: value computed is not used [-Wunused-value]