1 error[E0072]: recursive type `ListNode` has infinite size
5 | ^^^^^^^^^^^^^^^ recursive type has infinite size
7 LL | tail: Option<ListNode>,
8 | ---------------- recursive without indirection
10 help: insert some indirection to make `ListNode` representable
12 LL | tail: Box<Option<ListNode>>,
14 LL | tail: Rc<Option<ListNode>>,
16 LL | tail: &Option<ListNode>,
19 error: aborting due to previous error
21 For more information about this error, try `rustc --explain E0072`.