Compilare: user.cpp: In function ‘int main()’: user.cpp:79:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(x[ch] == 1) ^ user.cpp:81:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] x[ch] = 0; ^ user.cpp:85:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] x[ch] = 1; ^ user.cpp:109:45: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[k ++] = '0' + x[ S[j] ]; ^