Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:17:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<A[x].v.size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:27:7: warning: unused variable ‘x’ [-Wunused-variable] int i,x,y; ^ user.cpp:27:9: warning: unused variable ‘y’ [-Wunused-variable] int i,x,y; ^