Compilare: user.cpp: In function ‘char get(char)’: user.cpp:10:44: warning: array subscript has type ‘char’ [-Wchar-subscripts] for (char i=0;i<30;++i) if (i!=a && s[i]) return --s[i],i; ^ user.cpp:10:59: warning: array subscript has type ‘char’ [-Wchar-subscripts] for (char i=0;i<30;++i) if (i!=a && s[i]) return --s[i],i; ^ user.cpp:11:1: warning: control reaches end of non-void function [-Wreturn-type] } ^