cmpu-145 Spring 2019
Homework: Due 4/23.

1. Define the recursive factorial function.
;; FACTORIAL
;; ----------
;; INPUTS: N a non-negative integerN
;; OUTPUT: The value of N!

2. Define the combination function C(n,k) or "N-CHOOSE-K"

;; N-CHOOSE-K
;; ----------
;; INPUTS: N, K, non-negative integers with K <= N
;; OUTPUT: The value "N choose K", i.e., the number of
;;   combinations (without repetition) of K elements from a
;;   set of N elements: n!/(k!(n-k)!)

3. Define the permutation function P(n,k) or "N-PERM-K"

;; N-PERM-K
;; ----------
;; INPUTS: N, K, non-negative integers with K <= N
;; OUTPUT: The value P(n,k), i.e., the number of
;;   permutations (without repetition) of N elements from a
;;   set of N elements: n!/(n-k)!
;; (It might make more sense to implement this function before N-CHOOSE-K

4. Comment and test your code; it makes sense to use the asmt-helper.scm file
too. You can use submit145 to the hw7 directory.