[Solved] What will be the output of the following code?List list = new ArrayList(); list.add(5); list.add(10); System.out.println(list.get(0) + list.get(1)); | Java

Java - Wrapper Classes

What will be the output of the following code?

List list = new ArrayList<>();
list.add(5);
list.add(10);
System.out.println(list.get(0) + list.get(1));

A510

B15

CCompilation error

DRuntime error

Step-by-Step Solution

Solution:

Step 1: Understand autoboxing in collections
List stores Integer objects. Adding int values 5 and 10 autoboxes them to Integer objects.
Step 2: Evaluate the addition operation
list.get(0) and list.get(1) return Integer objects, which unbox to int when added, so 5 + 10 = 15.
Final Answer:
15 -> Option B
Quick Check:
Autoboxing/unboxing sums to 15 [OK]

Quick Trick: Autoboxing lets you add Integer values like ints [OK]

Common Mistakes:

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