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reborg/rand-remove.clj

Created May 10, 2017 13:52
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A few experiments for fast remove random element from a vector/list.
Raw
rand-remove.clj
(let [v [0 1 2 3 4 5 6 7]]
(quick-bench
(let [n (rand-int (count v))]
(doall (concat (take n v) (drop (inc n) v))))))
;; 804.634866 ns
(let [v [0 1 2 3 4 5 6 7]]
(quick-bench
(rest (shuffle v))))
;; 181.223551 ns
(let [v [0 1 2 3 4 5 6 7]]
(quick-bench
(pop (assoc v (rand-int (dec (count v))) (peek v)))))
;; 173.573571 ns
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