From: Emanuel Berg <incal@dataswamp.org>
To: help-gnu-emacs@gnu.org
Subject: Re: puzzle with string permutations [photo]
Date: Tue, 07 Jun 2022 10:08:53 +0200 [thread overview]
Message-ID: <87bkv4sxnu.fsf@dataswamp.org> (raw)
In-Reply-To: 87fskgsy4c.fsf@dataswamp.org
>>> (calc-eval "fact(5)") => "120"
>>> (calc-eval "fact(10)") => "3628800"
>>
>> Indeed, however that isn't lispy either ...
>
> (defun faculty (n)
> (if (> n 1)
> (* n (faculty (1- n)))
> 1) )
> ;; (faculty 5) ; 120
> ;; (faculty 10) ; 3 628 800
Perhaps better, as no recursion.
(require 'cl-lib)
(defun cl-faculty (n)
(cl-loop with prod = 1
for i from 2 to n do
(setq prod (* i prod))
finally return prod) )
;; (cl-faculty 5) ; 120
;; (cl-faculty 10) ; 3 628 800
--
underground experts united
https://dataswamp.org/~incal
next prev parent reply other threads:[~2022-06-07 8:08 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-07 6:39 puzzle with string permutations [photo] Emanuel Berg
2022-06-07 7:12 ` Marcin Borkowski
2022-06-07 7:54 ` Emanuel Berg
2022-06-07 7:58 ` Emanuel Berg
2022-06-07 8:08 ` Emanuel Berg [this message]
2022-06-07 13:53 ` Emanuel Berg
2022-06-07 14:18 ` Emanuel Berg
2022-06-07 16:09 ` Yuri Khan
2022-06-07 22:04 ` Emanuel Berg
2022-06-08 0:17 ` Emanuel Berg
2022-06-08 2:52 ` missing Lisp world (was: Re: puzzle with string permutations [photo]) Emanuel Berg
2022-06-07 8:37 ` puzzle with string permutations [photo] Emanuel Berg
2022-06-07 13:28 ` Emanuel Berg
2022-08-01 6:39 ` Marcin Borkowski
2022-08-01 7:39 ` Emanuel Berg
2022-08-02 12:21 ` Jean Louis
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