chrisvest-4clojure-solution74.clj

;; chrisvest's solution to http://4clojure.com/problem/74

(fn [s]
  (let [perfect-square
         (fn [n] (loop [i 1]
                       (cond
                         (= n (* i i)) true
                         (< n (* i i)) false
                         :else (recur (inc i)))))]
    (->> s
      (re-seq #"\d+")
      (map #(Integer/parseInt %))
      (filter perfect-square)
      (interpose ",")
      (apply str))))