Collections · interview question
The hottest operation in the code is have we already processed this orderId?. Which collection usually follows from that workload?
Multiple choiceMediumchapter-4-curatedpremiumcollectionschoosing-the-right-collection
Answer and explanation
Correct answer
A. A Set<String> for membership checks
Why
If membership testing and uniqueness dominate, a set is often the clearest fit. Strong collection reasoning follows the workload first and lets the structure choice follow from that.
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