Kotlin when Expressions

when is Kotlin's multi-way branch. Used without an argument, each branch is a Boolean condition, and the first one that is true supplies the result. else handles every remaining case.

fun grade(score: Int): String = when {
    score >= 90 -> "A"
    score >= 80 -> "B"
    else -> "C"
}

fun main() {
    println(grade(95))
    println(grade(82))
    println(grade(60))
}