reversed

Returns a progression that goes over the same range in the opposite direction with the same step.

fun IntProgression.reversed(): IntProgression(source)
val range = 1..5                 // 1, 2, 3, 4, 5
val reversed = range.reversed()  // 5, 4, 3, 2, 1

for (i in reversed) {
    println(i)
}

Source