kohyama

(require '[clojure.test :refer :all])

;; fizz-buzz
;; 連続整数列をリストとして与えると各要素に対して
;; 3 の倍数は "fizz" を
;; 5 の倍数は "buzz" を
;; 3 と 5 の両方の倍数の場合は "fizzbuzz" を出力し,
;; それ以外は何も出力しない, という法則で出力される文字列の順序集合を
;; リストとして返す.
(defn fizz-buzz [coll]

kohyama

(require '[clojure.test :refer :all])

(defn hanoi-states [n]
  (letfn [
    (hanoi [s t d n]
      (if (zero? n) '()
          (concat (hanoi s d t (dec n))
                  (list
                    (condp = [s d]
                      [0 2] (fn [[[h & a] b c]] [(if a a '()) b (cons h c)])

kohyama

(use 'clojure.test)

(defn fold-right [f z coll]
  (loop [[c & cs] coll rvsd '()]
    (if (nil? c)
        (loop [acc z [r & rs] rvsd]
          (if r (recur (f r acc) rs) acc))
        (recur cs (cons c rvsd)))))

(defn reduce-right [f coll]

kohyama

(import 'java.util.Date java.text.SimpleDateFormat)

(defn r-reduce [f coll retn pred]
    (loop [[c & cs :as curr] coll rvsd '()]
      (if (or (nil? c) (pred curr))
          (loop [acc (retn curr) [r & rs] rvsd]
            (if r (recur (f r acc) rs) acc))
          (recur cs (cons c rvsd)))))

(def sdf (SimpleDateFormat. "yyyy-MM-dd"))

kohyama

(use 'clojure.test)

(defn unfold
 "A variant of 'iterate' which accepts a stopping condition,
  having the same syntax as 'unfold' of scheme.
  Supposed
    (x1 x2 x3 ... xk-1 xk ... ) == (s (g s) (g (g s)) ... )
  and '(p xi)' returns true first at i == k,
    ((f x1) (f x2) (f x3) ... (f xk-1))
  is returned."

kohyama

(require '[clojure.test :refer :all])

(def s53
  ; If you are in 4clojure paste from here
  (fn [coll]
    (->> coll
      ; 1st. Make tails of coll.
      (#(take-while identity (iterate next %)))
      ; 2nd. Take only consecutive elements from the head for each list.
      (map (fn [[c & cs]]

kohyama

(defn fizz-buzz [n]
  (map #(cond (zero? (mod % 15)) "FizzBuzz"
              (zero? (mod % 5)) "Buzz"
              (zero? (mod % 3)) "Fizz"
              :else %)
       (range 1 (inc n))))

(fizz-buzz 100)
; -> (1 2 "Fizz" 4 "Buzz" "Fizz" 7 8 "Fizz" "Buzz" 11 "Fizz" 13 14 "FizzBuzz"
;     16 17 "Fizz" 19 "Buzz" "Fizz" 22 23 "Fizz" "Buzz" 26 "Fizz" 28 29 "FizzBuzz"

kohyama

(require '[clojure.test :refer (with-test are run-tests)])

(with-test
  (defn str-drop-while-same [& args]
    (if (some nil? args) args
        (->> (map #(concat % (repeat nil)) args)
          (apply map vector)
          (drop-while #(apply = %))
          (take-while #(some identity %))
          (apply map str))))

kohyama

(require '[clojure.test :refer (with-test are run-tests)])

(with-test
  (defn awtp [cs a]
    ((fn f [[h & r] a]
       (cond
         (zero? a) #{{}}
         (nil? h)  #{}
         :else     (set
                     (mapcat (fn [c]

kohyama

Clojure Exercises / Clojure 演習

Programming exercises frequently appeared / よくあるプログラミング課題

記述能力の高い Clojure.
よくあるプログラミングの演習問題を Clojure で解いてみます.

• FibBuzz
• 整列アルゴリズム
• N Queen Problem / N クイーン問題