Tests failing on Hackerrank but answer correct

Question

I have the following solution:

(defn count-swaps [a]
  (letfn [(swap [a i j] ;; looked up letfn online
            (assoc a i (nth a j) j (nth a i)))]
    (loop [a a num-swaps 0 i 0]
      (if (< i (count a))
        (let [int-loop (loop [a' a j 0 num-swaps' 0]
                         (if (< j (dec (count a)))
                           (if (> (nth a j) (nth a (inc j)))
                             (recur (swap a' j (inc j)) (inc j) (inc num-swaps'))
                             (recur a' (inc j) num-swaps'))
                           [a' num-swaps']))]
          (recur (nth int-loop 0) (+ num-swaps (nth int-loop 1)) (inc i)))
        [num-swaps (nth a 0) (nth a (dec (count a)))]))))

(let [result (count-swaps [4 2 3 1])]
  (prn (str "Array is sorted in " (nth result 0) " swaps.") )
  (prn (str "First Element: " (nth result 1)) )
  (prn (str "Last Element: " (nth result 2)))
  )

For this problem: https://www.hackerrank.com/challenges/ctci-bubble-sort/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=sorting

However, upon running submitting the problem, none of the tests pass. I don't know why.

Answer 1

after testing this for about an hour or so, I realized where you're mistaken. Namely, using prn instead of print prints out the quote characters alongside the actual text. This was a surprise to me, since I always thought that these two are interchangeable. If you change your prns to printlns, you should be okay.

The final code that I created which passed all of the tests:

;
; Complete the 'countSwaps' function below.
;
; The function accepts INTEGER_ARRAY a as parameter.
;

(defn count-swaps [a]
  (letfn [(swap [a i j] ;; looked up letfn online
            (assoc a i (nth a j) j (nth a i)))]
    (let [result (loop [a a num-swaps 0 i 0]
      (if (< i (count a))
        (let [int-loop (loop [a' a j 0 num-swaps' 0]
                         (if (< j (dec (count a)))
                           (if (> (nth a j) (nth a (inc j)))
                             (recur (swap a' j (inc j)) (inc j) (inc num-swaps'))
                             (recur a' (inc j) num-swaps'))
                           [a' num-swaps']))]
          (recur (nth int-loop 0) (+ num-swaps (nth int-loop 1)) (inc i)))
        [num-swaps (nth a 0) (nth a (dec (count a)))]))]
  (println (str "Array is sorted in " (nth result 0) " swaps.") )
  (println (str "First Element: " (nth result 1)))
  (println (str "Last Element: " (nth result 2))))))

(def n (Integer/parseInt (clojure.string/trim (read-line))))

(def a (vec (map #(Integer/parseInt %) (clojure.string/split (clojure.string/trimr (read-line)) #" "))))

(count-swaps a)

Let me know if you need any further clearance on this.