; A cheap source of very low quality random numbers.
(library (random)
  (export random-integer random-real)
  (import (rnrs))
  (define prime1 16708)
  (define prime2 2147483647)
  (define (make-generator seed)
    (let ([seed seed])
      (lambda ()
        (set! seed (modulo (* seed prime1) prime2))
        seed)))
  (define generate (make-generator prime1))
  (define (random-integer n)
    (modulo (generate) n))
  (define (random-real)
    (exact->inexact (/ (generate) prime2))))