(load "constraints.txt")

 (averager a b c)
  (let ((s (make-connector))
        (d (make-connector)))
    (adder a b s)
    (constant 2 d)
    (multiplier c d s)
    'ok))



; 1 ]=> (define a (make-connector))
; 
; ;Value: a
; 
; 1 ]=> (define b (make-connector))
; 
; ;Value: b
; 
; 1 ]=> (define c (make-connector))
; 
; ;Value: c
; 
; 1 ]=> (averager a b c)
; 
; ;Value: ok
; 
; 1 ]=> (probe "a" a)
; 
; ;Value: #[compound-procedure 12 me]
; 
; 1 ]=> (probe "b" b)
; 
; ;Value: #[compound-procedure 13 me]
; 
; 1 ]=> (probe "c" c)
; 
; ;Value: #[compound-procedure 14 me]
; 
; 1 ]=> (set-value! a 5 'user)
; 
; Probe: a = 5
; ;Value: done
; 
; 1 ]=> (set-value! b 10 'user)
; 
; Probe: b = 10
; Probe: c = 15/2
; ;Value: done
; 
; 1 ]=> (forget-value! a 'user)
; 
; Probe: a = ?
; Probe: c = ?
; ;Value: done
; 
; 1 ]=> (set-value! c 20 'user)
; 
; Probe: c = 20
; Probe: a = 30
; ;Value: done