[Solved] What will be the output of this Kotlin code?class Counter(var count: Int) { operator fun inc(): Counter { count++ return this } } fun main() { var c = Counter(10) println(c++) println(c.count) } | Kotlin

Kotlin - Operators and Expressions

What will be the output of this Kotlin code?

class Counter(var count: Int) {
  operator fun inc(): Counter {
    count++
    return this
  }
}

fun main() {
  var c = Counter(10)
  println(c++)
  println(c.count)
}

AError: inc operator must return new object

B10 and 11

C11 and 11

DCounter@hashcode and 11

Step-by-Step Solution

Solution:

Step 1: Understand post-increment behavior
c++ prints the object before increment, so it prints the object reference (like Counter@hashcode).
Step 2: Check count after increment
After c++, count is incremented to 11, so c.count prints 11.
Final Answer:
Counter@hashcode and 11 -> Option D
Quick Check:
Post-increment prints object then increments count [OK]

Quick Trick: Post-increment returns old value, then increments [OK]

Common Mistakes:

MISTAKES

Expecting count before increment on second print
Thinking inc must return new object always
Confusing pre-increment and post-increment

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What will be the output of this Kotlin code?

Step 1: Understand post-increment behavior

Step 2: Check count after increment

Final Answer:

Quick Check:

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