Abstract List Functions:
Using abstract list functions, write a function, string-num, that consumes a list of number, lon, and
produces a single string that contains all the numbers in lon, in the order that they appear in the list.
;; (string-num empty) => “”
;; (string-num (list 1)) => “1”
;; (string-num (list 4 0.6 54 -9.9) => “40.654-9.9”
Mutation:
(define-struct children (total girl boy))
;; A children is a structure (make-children (t g b)) where
;; t is an integer representing the total number of children in a family,
;; g is an integer representing the number of girls in the family, and
;; b is an integer representing the number of boys in the family.
Write a function, update-family, that consumes a children structure, c, and a symbol, gender, which is
either ‘girl or ‘boy, and mutates the structure to account for a new baby being born into a family. It will
increase the total number of children by 1, and increase either the girl or the boy field by one depending
on whether gender is ‘girl or ‘boy. It will produce the string “This family used to have x children.” where
x is the total number of children before it was mutated.
Example:
;; (define f (make-children 3 2 1))
;; If we call (update-family f ‘boy), the total number of children is now 4, the number of girls is still 2,
;; and the number of boys is now 2. It will produce “This family used to have 3 children.”
Strings in Python:
Write a function, telephone_number, that consumes a string, number, that contains exactly 10 natural
numbers with a space between each number and produces a string in the form “###-###-####”, where
the first group is the first three numbers, the second group is the fourth, fifth and sixth number, and the
last group is the last four numbers.
Example: # telephone_nu

More
Less