Compilare: main.cpp: In function 'int main()': main.cpp:25:18: warning: array subscript has type 'char' [-Wchar-subscripts] freq[s[i]]++; ^ main.cpp:40:25: warning: array subscript has type 'char' [-Wchar-subscripts] if (put_let[s[i]] == put_maxim) ^ main.cpp:49:34: warning: array subscript has type 'char' [-Wchar-subscripts] v[j].a = j - put_let[s[j]]; ^ main.cpp:50:34: warning: array subscript has type 'char' [-Wchar-subscripts] v[j].b = j + put_let[s[j]]; ^