Compilare: user.cpp: In function ‘void dfs2(int, int)’: user.cpp:33:9: warning: unused variable ‘x’ [-Wunused-variable] int x,prev; //cin>>x; ^ user.cpp:33:11: warning: variable ‘prev’ set but not used [-Wunused-but-set-variable] int x,prev; //cin>>x; ^ user.cpp: In function ‘int main()’: user.cpp:82:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y; ^