【SICP习题】113 练习3.33
【SICP练习】113 练习3.33
练习3-33
原文
Exercise 3.33. Using primitive multiplier, adder, and constant constraints, define a procedure averager that takes three connectors a, b, and c as inputs and establishes the constraint that the value of c is the average of the values of a and b.
代码
(define (averager a b c)
(let ((sum (make-connector))
(d (make-connector)))
(adder a b sum)
(multiplier sum d c)
(constant (/ 1 2) d)
'ok))