Collections · interview question
Consider the following code snippet. What will be the output? HashMap<String, Integer> map = new HashMap<>(); map.put('A', 1); map.put('B', 2); map.put('A', 3); System.out.println(map.get('A'));?
Multiple choiceHardchapter-4-curatedpremiumcollectionsmap-interface-and-hashmap
HashMap<String, Integer> map = new HashMap<>();
map.put('A', 1);
map.put('B', 2);
map.put('A', 3);
System.out.println(map.get('A'));Answer and explanation
Correct answer
C. 3
Why
The output will be 3. When a new value is put into a map with an existing key, the old value is replaced. Thus, 'A' maps to 3 after the final put() call.
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