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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp
Subject: Rosetta Code: Dinesman's multiple-dwelling problem
Date: Mon, 5 Aug 2024 20:38:43 -0000 (UTC)
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> The problem
> 
>   Baker, Cooper, Fletcher, Miller, and Smith live on different
>   floors of an apartment house that contains only five floors.
> 
>   Baker does not live on the top floor. 
>   Cooper does not live on the bottom floor. 
>   Fletcher does not live on either the top or the bottom floor. 
>   Miller lives on a higher floor than does Cooper. 
>   Smith does not live on a floor adjacent to Fletcher's. 
>   Fletcher does not live on a floor adjacent to Cooper's. 
> 
> Where does everyone live?

newLISP

;; Iterate over all permutations of a list, and
;; call a function on each.
(define (permute permute.seq permute.func (permute.built '()))
  (if (null? permute.seq)
    (permute.func permute.built)
    (let (seq (copy permute.seq))
      (dotimes (i (length seq))
        (unless (zero? i) (rotate seq -1))
        (permute
          (rest seq)
          permute.func
          (cons (first seq) permute.built))))))

(define (adjacent a b lst)
  (= 1 (abs (- (find a lst)
               (find b lst)))))

(define (check lst)
  (if
    (and
      (< (find 'baker lst) 4)
      (> (find 'cooper lst) 0)
      (not (member (find 'fletcher lst) '(0 4)))
      (> (find 'miller lst) (find 'cooper lst))
      (not (adjacent 'smith 'fletcher lst))
      (not (adjacent 'cooper 'fletcher lst)))
    (println lst)))

(permute '(baker cooper fletcher miller smith) check)
  ===>
(smith cooper baker fletcher miller)