Nth Element – Rich 4Clojure Problem 21 – See: https://github.com/PEZ/rich4clojure

rich4clojure_easy_problem_021.clj

(ns rich4clojure.easy.problem-021
  (:require [hyperfiddle.rcf :refer [tests]]))

;; = Nth Element =
;; By 4Clojure user: dbyrne
;; Difficulty: Easy
;; Tags: [seqs core-functions]
;; 
;; Write a function which returns the Nth element from a
;; sequence.

(def restricted [nth])

(def __ :tests-will-fail)

(comment
  
  )

(tests
  (__ '(4 5 6 7) 2) := 6
  (__ [:a :b :c] 0) := :a
  (__ [1 2 3 4] 1) := 2
  (__ '([1 2] [3 4] [5 6]) 2) := [5 6])

;; To participate, fork:
;; https://github.com/PEZ/rich4clojure

;; Post your solution below, please!

(fn [seq el] (nth seq el))
or
#(nth %1 %2)

#(first (drop %2 %1))

(fn [sq n-index]
(get (vec sq) n-index))

(def nth' (fn [s n]
            (->> s
                (drop n)
                first)))

(fn [coll n]
          (loop [x coll
                 cnt 0]
            (if (= cnt n)
              (first x)
              (recur (rest x) (+ cnt 1)))))

(defn n-th-1 [coll n]
(def ans (n-th coll n 0))
ans)

(defn n-th [coll n c]
(if (== c n)
(first coll)
(recur (rest coll) n (inc c)))
)