Compilare: user.cpp: In function ‘int main()’: user.cpp:11:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[ch]++; ^ user.cpp:17:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(v[ch]>0&&ch!=ca){ ^ user.cpp:23:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(v[ch]>=nr/2+1){ ^ user.cpp:29:8: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[c]--; ^