Collections · interview question
Why might a HashSet not prevent duplicates as expected when using custom objects?
Multiple choiceHardchapter-4-curatedpremiumcollectionsset-interface-and-hashset
Answer and explanation
Correct answer
C. HashCode() is overridden but equals() is not.
Why
If hashCode() is overridden but equals() is not, or vice versa, the HashSet may not correctly identify duplicates. Both methods need to be properly implemented to ensure the set's uniqueness contract is maintained.
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