Collections · interview question
Which Java collection should you choose for a product catalog if you need to frequently check if a product ID exists and order does not matter?
Multiple choiceMediumchapter-4-curatedpremiumcollectionscollection-performance-basics
Answer and explanation
Correct answer
C. HashSet
Why
A HashSet provides O(1) average time complexity for contains operations, which is ideal when you frequently check for the existence of elements and do not care about order.
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