(defun permutation-count (n c)
(let ((ans 1))
(loop for i from (- n (1- c)) upto n do (setf ans (* ans i))) ans))
(format t "~D~%" (permutation-count 6 5))
(defun permutation-count (n c)
(let ((ans 1))
(loop for i from (- n (1- c)) upto n do (setf ans (* ans i))) ans))
(format t "~D~%" (permutation-count 6 5))
Author: ismdeep
Permalink: https://ismdeep.com/posts/2019-01-26-calculate-permutation-count.html
License: Copyright (c) 2021 CC-BY-NC-4.0 LICENSE