Stocking draws

stocking.rkt

#lang racket

(define people '(liz steve aj marti david ann pat annie mae helen jane carl
                     sam katie will lindsey
                     ))


(define last-year '((sam aj) (katie will) (liz jane) (aj liz) (steve marti) (pat steve) (mae katie)
                             (ann annie) (helen mae) (carl helen) (jane david) (annie carl)
                             (will sam) (david pat) (marti ann)))

(define cousins '(mae helen jane carl annie will katie sam lindsey))

(define cousins-last-year '((helen katie) (carl mae) (will sam) (annie helen) (jane annie) (katie jane) (sam carl) (mae will)))
(define cousins-siblings (let ([l '((helen jane) 
                                    (helen carl)
                                    (jane carl)
                                    (sam mae)                                    
                                    (sam katie)
                                    (mae katie)
                                    (will annie)
                                    (will lindsey)
                                    (annie lindsey))])
                           (append l (map reverse l))))


(define (run people last-year)
  (let loop ([from (shuffle people)] [to (shuffle people)] [so-far null])
    (cond [(null? from) so-far]
          [(eq? (first from) (first to))
           (loop (shuffle from) (shuffle to) so-far)]
          [(or (member (list (first from) (first to)) last-year))
           (loop (shuffle from) (shuffle to) so-far)]
          [(member (list (first to) (first from)) so-far)
           (loop (shuffle from) (shuffle to) so-far)]
          [else
           (displayln (list (first from) (first to)))
           (displayln (list from to))
           (loop (rest from) (rest to) (cons (list (first from) (first to)) so-far))])))

;; stocking draw results
(define l
  '((ann marti)
    (helen annie)
    (jane mae)
    (carl david)
    (aj helen)
    (david ann)
    (liz carl)
    (annie pat)
    (mae aj)
    (marti steve)
    (pat liz)
    (steve jane)))


(define (stocking-print)
  (for ([pr l])
    (printf "~a has ~a's stocking\n"
            (string-titlecase (symbol->string (first pr)))
            (string-titlecase (symbol->string (second pr))))))

(define cousin-draw
  '((mae carl)
  (carl katie)
  (jane sam)
  (katie will)
  (annie mae)
  (will helen)
  (helen annie)
  (sam lindsey)
  (lindsey jane)))

(define (cousin-print)
  (for ([pr cousin-draw])
    (printf "~a has ~a\n"
            (string-titlecase (symbol->string (first pr)))
            (string-titlecase (symbol->string (second pr))))))