;;;; amb-pythagorean.scm
;;;; From "Continuations by example" ..." by Matt Might

(import scheme)
(import (chicken base))
(import amb)
(import amb-extras)

(define (pythagorean)
  ;
  (let ((a (amb 1 2 3 4 5 6 7))
        (b (amb 1 2 3 4 5 6 7))
        (c (amb 1 2 3 4 5 6 7)) )
    ;
    ; We're looking for dimensions of a legal right
    ; triangle using the Pythagorean theorem:
    ;
    (amb-assert (= (* c c) (+ (* a a) (* b b))))
    ;
    ; And, we want the second side to be the shorter one:
    ;
    (amb-assert (< b a))
    ;
    ; the answer:
    ;
    (list a b c) ) )