Compilare: main.cpp: In function 'int main()': main.cpp:46:16: warning: array subscript has type 'char' [-Wchar-subscripts] fr[s[i]]++; ^ main.cpp:92:31: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr0*fr[change(s[b])]+nr1*fr[s[b]]; ^ main.cpp:92:44: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr0*fr[change(s[b])]+nr1*fr[s[b]]; ^ main.cpp:94:35: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr1*fr[change(s[b])]+nr0*fr[s[b]]; ^ main.cpp:94:48: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr1*fr[change(s[b])]+nr0*fr[s[b]]; ^