intermediateCollections Framework

When should you choose ArrayList over LinkedList (and vice versa)?

Almost always ArrayList — get(index) is O(1) vs O(n) for LinkedList, and contiguous memory gives far better CPU cache locality (a real benchmark: getting a middle element from 10 million items takes ~1ms on ArrayList vs ~125ms on LinkedList). LinkedList only wins for frequent inserts/removals at the head.

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