Compilare: main.cpp: In function 'int main()': main.cpp:52:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<dim; i++) ~^~~~ main.cpp:54:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=dim; i<2*dim; i++) ~^~~~~~ main.cpp:56:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<dim; i++) ~^~~~ main.cpp:62:16: warning: array subscript has type 'char' [-Wchar-subscripts] fr[s[i]]++; ^ main.cpp:109:35: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr0*fr[change(s[b])]+nr1*fr[s[b]]; ^ main.cpp:109:48: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr0*fr[change(s[b])]+nr1*fr[s[b]]; ^ main.cpp:111:35: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr1*fr[change(s[b])]+nr0*fr[s[b]]; ^ main.cpp:111:48: warning: array subscript has type 'char' [-Wchar-subscripts] nr=nr1*fr[change(s[b])]+nr0*fr[s[b]]; ^