[Solved] Given the following Kotlin code, what will be the output?val map = mutableMapOf("a" to 1, "b" to 2) map["a"] = 3 println(map)Explain why this works even though map is declared with val. | Kotlin

Kotlin - Variables and Type System

Given the following Kotlin code, what will be the output?

val map = mutableMapOf("a" to 1, "b" to 2)
map["a"] = 3
println(map)

Explain why this works even though map is declared with val.

A{a=3, b=2}

B{a=1, b=2}

CCompilation error: cannot modify val map

DRuntime error

Step-by-Step Solution

Solution:

Step 1: Understand val with mutable collections
val means the reference to the map cannot change, but the map's content can be modified.
Step 2: Analyze the map update
Updating key "a" to 3 changes the map content, so printing shows {a=3, b=2}.
Final Answer:
{a=3, b=2} -> Option A
Quick Check:
val reference + mutable map = updated map content [OK]

Quick Trick: val fixes reference, mutable map content can change [OK]

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