Compilare: user.cpp: In function ‘int compare(char*, char*, int, int)’: user.cpp:39:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(vcar[a[i]]!=b[i] && vcar[a[i]]!=0) ^ user.cpp:39:45: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(vcar[a[i]]!=b[i] && vcar[a[i]]!=0) ^ user.cpp:48:26: warning: array subscript has type ‘char’ [-Wchar-subscripts] vcar[a[i]]=b[i]; ^