Compilare: user.cpp: In function ‘int main()’: user.cpp:22:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] s[x]++; ^ user.cpp:25:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] s[x]--; ^ user.cpp:26:15: warning: array subscript has type ‘char’ [-Wchar-subscripts] need[x]++; ^ user.cpp:39:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if ( need[x] ) ^ user.cpp:41:59: warning: array subscript has type ‘char’ [-Wchar-subscripts] if ( !r.empty() && x <= r.back() && s[r.back()] ) ^ user.cpp:43:30: warning: array subscript has type ‘char’ [-Wchar-subscripts] need[r.back()]++; ^ user.cpp:44:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] s[r.back()]--; ^ user.cpp:49:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] need[x]--; ^ user.cpp:54:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] --s[x]; ^