Quick Answer
ArrayList: backed by an array, O(1) random access by index, O(n) insertion/deletion in the middle (elements shift), fast iteration. LinkedList: doubly-linked list, O(1) insertion/deletion at head/tail, O(n) random access, more memory (stores pointers). Choose ArrayList for most cases. Use LinkedList only when you frequently add/remove from both ends.
Answer
ArrayList: Backed by array; fast random access; slower insert/delete in middle. LinkedList: Doubly linked nodes; fast insert/delete; slow random access.
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SugharaIQ Editorial Team
Verified Answer
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