prime sieve

s.hy

#!/usr/bin/env hy
(def N 999)
(def a (+ [1 1] (* [0] N)))
(let [(i 1) (j 0)]
  (while (< i N)
    (if (= i j)   (print i))
    (cond
      [(> j N)    (setv j 0)]
      [(>= j i)   (do (setv (get a j) 1)
                      (setv j (+ j i)))]
      [(get a i)  (setv i (inc i))]
      [true       (setv j i)])))