Re: Given string 'a.bc.' -- replace each dot(.) with 0 or 1

On 5/18/2024, HenHanna wrote:

-- Given a string  'a.bc.'   -- replace each dot(.)  with 0 or 1.
 
       -- So the value is a list of 4 strings:
                                 ('a0bc0'  'a0bc1'  'a1bc0'  'a1bc1')
 
-- The order is not important.
            If the string has 3 dots, the value is a list of length 8.

Gauche Scheme:

(use srfi-13)  ;; string-count
(use util.combinations)  ;; cartesian-product

(define (dot s)
  (let ((b (cartesian-product (make-list (string-count s #\.) '(0 1))))
        (fs (regexp-replace-all "[.]" s "~d")))
    (map (cut apply format fs <>) b)))

(dot "a.b.c")
  ===>
("a0b0c" "a0b1c" "a1b0c" "a1b1c")

(dot "a.b")
  ===>
("a0b" "a1b")

(dot "ab.")
  ===>
("ab0" "ab1")

(dot ".ab")
  ===>
("0ab" "1ab")

(dot "ab")
  ===>
("ab")