[4Clojure]解题记录-#78

Reimplement Trampoline

 

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Difficulty:	Medium
Topics:	core-functions

 

Reimplement the function described in "Intro to Trampoline".

 

(= (letfn [(triple [x] #(sub-two (* 3 x)))

          (sub-two [x] #(stop?(- x 2)))

          (stop? [x] (if (> x 50) x #(triple x)))]  (__ triple 2))  82)

 

(= (letfn [(my-even? [x] (if (zero? x) true #(my-odd? (dec x))))

          (my-odd? [x] (if (zero? x) false #(my-even? (dec x))))]

    (map (partial __ my-even?) (range 6)))  [true false true false true false])

 

解长度 41：

#(loop [t (apply % %&)] (if (fn? t) (recur (t)) t))