Naive Implementation of rotate left and rotate right.

gistfile1.txt

(defn rotatel
  ([n col]
  (let [n (mod n (count col))]
    (concat
     (drop n col)
     (take n col))))
  ([col]
     (rotatel 1 col)))

(defn rotater
  ([n col]
  (let [n (mod n (count col))]
    (concat
     (take-last n col)
     (drop-last n col))))
  ([col]
  (rotater 1 col)))