Compilare: user.cpp: In function ‘bool getval()’: user.cpp:39:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] t=t^val[a[i]];cuv();is(); ^ user.cpp: In function ‘int main()’: user.cpp:50:14: warning: array subscript has type ‘char’ [-Wchar-subscripts] val[o]=!val[o]; ^ user.cpp:50:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] val[o]=!val[o]; ^