Compilare: main.cpp: In function 'int main()': main.cpp:19:20: warning: array subscript has type 'char' [-Wchar-subscripts] if (in[s[i]] == 0) { ^ main.cpp:23:20: warning: array subscript has type 'char' [-Wchar-subscripts] in[s[i]] = nr_lit; ^ main.cpp:26:25: warning: array subscript has type 'char' [-Wchar-subscripts] ++ap[in[s[i]]]; ^