chapter1-is-unique

(ns BristolClojurians.interview
  (:require [clojure.test :refer [deftest is]])
  (:gen-class))

;; set is allowed
(defn unique? [string]
  (= string (apply str (set string))))

(deftest unique?-test
  (is (= true (unique? "abc")))
  (is (= false (unique? "test"))))

(defn unique-loop? [string]
  (loop [acc []
         word string]
    (cond
      (empty? word) true
      (some (partial = (first word)) acc) false
      :else (recur (conj acc (first word)) (rest word)))))

(deftest unique-loop?-test
  (is (= (unique-loop? "") true))
  (is (= (unique-loop? "abc") true))
  (is (= (unique-loop? "test") false)))

(defn unique-frequencies? [string]
  (filter #{1 0} (frequencies string)))

(comment
  (mapv (comp #(< % 2) val) (frequencies "test")))

(comment
  (apply max (mapv val (frequencies "test"))))

(comment
  (boolean (seq (filter (comp #(<= 2 %) val) (frequencies "tes")))))