Compilare: main.c: In function 'main': main.c:25:11: warning: array subscript has type 'char' [-Wchar-subscripts] fa[a[n]]++; ^ main.c:39:48: warning: array subscript has type 'char' [-Wchar-subscripts] while( t >= 0 && a[i] < top() && fb[a[i]] > 0 && fa[top()] - 1 >= fb[top()] ) { ^ main.c:43:19: warning: array subscript has type 'char' [-Wchar-subscripts] if( fb[a[i]] ) { ^ main.c:45:19: warning: array subscript has type 'char' [-Wchar-subscripts] fb[a[i]]--; ^ main.c:47:15: warning: array subscript has type 'char' [-Wchar-subscripts] fa[a[i]]--; ^