ズンドコ問題

zundoko.rkt

#lang racket

(define (take-upto length lst)
 (cond
   [(<= length 0) null]
   [(null? lst) null]
   [else (cons (first lst)
               (take-upto (sub1 length) (rest lst)))]))

(define (zundoko)
  (define (rec history)
    (if (equal? history (list 1 0 0 0 0)) ; ドコ ズン ズン ズン ズン
        (displayln "キ・ヨ・シ！")
        (let ([i (random 2)])
          (display (vector-ref (vector "ズン" "ドコ") i))
          (rec (take-upto 5 (cons i history))))))
  (rec null))

(zundoko)