A LinkedList self-check tests endpoint operations, overloaded removal, iterator ownership and traversal cost.
Review the contracts
Review LinkedList contracts, iterator edits, indexed storage before answering.
Choose and explain an answer
Identify the selected overload, the empty-list policy and who owns the edit before choosing an answer. A matching output on a populated list does not establish the empty-input contract.
Select an answer for every question, then check the result and read each explanation. Progress remains in this browser; this is a self-check, not a judged program submission or a credential.
Common Mistakes
An int argument can mean a position rather than a stored Integer. A null return is not the same behavior as an exception.