JuniorTheoryCommon

What does the program print?

KOTLIN

fun main() {
    var count = 0
    val tick = { count += 1 }
    tick()
    tick()
    println(count)
}

Expecting 0: a lambda does not get a copy of count. It remembers the variable itself, so both calls change the count that println reads.
Expecting the body to run when the lambda is created: val tick = { count += 1 } only stores it, so count grows only on the two tick() calls.

JuniorTheoryCommon

KOTLIN

fun main() {
    var count = 0
    val tick = { count += 1 }
    tick()
    tick()
    println(count)
}

Expecting 0: a lambda does not get a copy of count. It remembers the variable itself, so both calls change the count that println reads.
Expecting the body to run when the lambda is created: val tick = { count += 1 } only stores it, so count grows only on the two tick() calls.