Compilare: user.cpp: In function ‘nod* add_child(nod*, char)’: user.cpp:20:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!n->copii[ch]){ ^ user.cpp:21:14: warning: array subscript has type ‘char’ [-Wchar-subscripts] n->copii[ch] = new nod; } ^ user.cpp:22:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] return n->copii[ch]; } ^ user.cpp: In function ‘nod* update_persistent(const nod*, int)’: user.cpp:30:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] cur->copii[ch] = add_child(cur, ch); ^ user.cpp:33:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] cur = cur->copii[ch]; ^ user.cpp:34:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] n = n->copii[ch]; ^