Sunday, January 12, 2014

99 Clojure Problems – 3: Find the Kth Element of a List


(deftest p03-kth
  (is (= 3 (kth 2 (list 1 2 3 4)))))


There is a built-in function called nth that solves this problem.


A relatively straightforward recursive solution uses recur on the function itself while decrementing the k and dropping the first element on each recursive call until we reach k = 0 at which point we return the first element. Strictly speaking this is a linear iterative process and not a recursive one as all the state of the process is in its parameter bindings and not in the results of the stack of recursive calls.

Read more about this series.

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