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2 points by almkglor 6139 days ago | link | parent

  (def valid? (stack)
    (let i 0
      (if (or (pos stack.0 cdr.stack)
              (some [do (++ i) (is i (abs:- _ stack.0))] cdr.stack))
        nil
        t)))


1 point by map 6138 days ago | link

  (def valid? (stack)
    (let i 0
      (if (or (pos stack.0 cdr.stack)
              (some [is ++.i (abs:- stack.0 _)] cdr.stack))
        nil
        t)))

  (def queens (stack n)
    (if (is n 8)
      (do (prall rev.stack "[ ") (prn " ]"))
      (for rank 1 8
        (push rank stack)
        (if (valid? stack)
            (queens stack (+ n 1)))
        (pop stack))))

  (queens '() 0)

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