or even

fun testFun(nums: IntArray) =
    nums.fold(Int.MIN_VALUE to Int.MAX_VALUE) { (largest, smallest), next ->
        max(largest, next) to min(smallest, next)
    }.run { first - second }

thanks, i did not even know about the

run

function.

Why not just:

fun testFun(nums: IntArray): Int {
    return nums.max()!! - nums.min()!!
}

to avoid additional run over the collection

Ok sure, if it’s a large list. Is it?

how does @Uzi Landsmann solution does additional run over? @Dias do both

nums.max()!!

and

nums.min()!!

iterates through the whole list

Yes they do. If your list is large then you should consider a different solution.