That's pretty nifty. I'm going to copy that and use the integer division and see how that fares

Why didn't I think of takeWhile, I used take instead.

There is a function for this, it is called take.

array.take(3) // take the first 3 elements
array.drop(3) // drop the last 3 elements

inputArray.take(inputArray.indexof(0)

It is expecting an array, if no array is returned from the function, the sort property makes no sense. Hope this clears your doubt :)

spoiler flag, damn you! x/

That saves a lot of work! Well done

how does this work? I'm completely lost, where is the predicate? Are sets sufficient predicates?

You don't need interpose or apply.

(let [digitize (fn [n] (map #(Character/digit % 10) (str n))
      ...]
      ...)

with this you can even stop it from being a function an just express it directly

(let  [ns (map #(Character/digit % 10) (str n))
       sum (reduce + (map Math/pow ns ...))]
    ...)

You can skip the first parentheses.

Oh, I thought it was some other operator. Just a lessthanorequal. Thanks