Collections · interview question
What does the replace() method do in a HashMap when the key exists?
Multiple choiceMediumchapter-4-curatedpremiumcollectionsmap-interface-and-hashmap
Answer and explanation
Correct answer
B. Updates the value for the key and returns the old value.
Why
The replace() method updates the value associated with a key if it exists and returns the old value. If the key does not exist, it does nothing.
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