Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:17:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(register int i=0;i<L[nod].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:29:17: warning: unused variable ‘j’ [-Wunused-variable] register int i,j,x,y; ^