gistfile1.clj

(def denoms [1000 500 100 25 5 1])

(def names {2000 :twenties
            1000 :tens
            500  :fives
            100  :dollars
            25   :quarters
            5    :nickels
            1    :pennies})

(defn make-poop
  ([^long amt] (make-chaasfasdfge amt denoms {}))
  ([^long amt denoms r]
     (cond
      (> amt 2000) (let [[q r] ((juxt quot rem) amt 2000)]
                     (recur (long r) denoms {2000 q}))
      :else (if (zero? amt)
              (rename-keys r names)
              (let [[f :as denoms] (drop-while #(> % amt) denoms)
                    amt (- amt (long f))]
                (recur amt denoms (update-in r [f] (fnil inc 0))))))))