(define (reversed-digits n)
  (cond ((<= n 0) '())
        (else (cons n (reversed-digits (- n 1))))))

(define (digits n)
  (reverse (reversed-digits n)))

;; test digits
(digits 10)
(digits 0)

;; Removes every occurance of symbol s from the list l
(define (remove s l)
  (cond ((null? l) '())
        ((eq? s (car l)) (remove s (cdr l)))
        (else (cons (car l) (remove s (cdr l))))))

;; test remove
(remove 3 '(0 1 2 3 4 5))
(remove 0 '(0 1 2 3 4 5))
(remove 9 '(0 1 2 3 4 5))


;; draws and returns k random symbols from the list l
(define (draw k l)
  (cond ((<= k 0) '())
        ((null? l) '())
        (else (let ((s (list-ref l (random (length l)))))
                (cons s (draw (- k 1) (remove s l)))))))

(draw 5 (digits 55))

(define (number-to-rank n)
  (cond ((eq? n  1) 'A)
        ((eq? n 11) 'J)
        ((eq? n 12) 'Q)
        ((eq? n 13) 'K)
        (else n)))

(define (number-to-suit n)
  (cond ((eq? n 1) 'C)
        ((eq? n 2) 'D)
        ((eq? n 3) 'H)
        ((eq? n 4) 'S)
        (else n)))

;; make-card creates a dotted pair that represents the card of a given numerical rank and suit.
(define (make-card n suit)
  (cons (number-to-rank n) (number-to-suit suit)))

;; generate-suit returns a list that contains 13 cards in the specified suit.
(define (generate-suit suit)
  (map (lambda (x) (make-card x suit)) 
       (digits 13)))

;; test generate-suit
(generate-suit 'H)
(generate-suit 3)


(define *deck*
  (append (generate-suit 'C) (generate-suit 'D) (generate-suit 'H) (generate-suit 'S)))
          
(define (deal)
  (draw 5 *deck*))

(deal)