prisoner.scm

(define (prisoner strtegy-1 strtegy-2)
  (cond [(and strtegy-1 strtegy-2) (values -6 -6)]
  [(or  strtegy-1 strtegy-2)
	 (if strtegy-1 (values -0 -9) (values -9 -0))]
	[(and (not strtegy-1) (not strtegy-2)) (values -1 -1)]))
(prisoner #t #t)
(prisoner #f #t)
(prisoner #t #f)
(prisoner #f #f)

;;パターンマッチ
(use util.match)
(define (prisoner . strtegies)
  (match strtegies
	 [(#t #t) '(-6 -6)]
	 [(#t #f) '(-0 -9)]
	 [(#f #t) '(-9 -0)]
	 [(#f #f) '(-1 -1)]))

(prisoner #t #t)
(prisoner #f #t)
(prisoner #t #f)
(prisoner #f #f)

;;パターンマッチ2
(use util.match)
(define (prisoner strtegy-1 strtegy-2)
  (match (list strtegy-1 strtegy-2)
	 [("m" "m") `((payoff-1 . 6) (payoff-2 . 6))]
	 [("m" "f") `((payoff-1 . 0) (payoff-2 . 9))]
	 [("f" "m") `((payoff-1 . 9) (payoff-2 . 0))]
	 [("f" "f") `((payoff-1 . 1) (payoff-2 . 1))]))