(define (rand-update x)
  (modulo (+ (* 214013 x) 2531011) (expt 2 32)))

(define rand
  (let ((x 1))
    (lambda (n)
      (cond ((eq? n 'generate)
             (begin (set! x (rand-update x))
                    x))
            ((eq? n 'reset)
             (lambda (new-value)
               (set! x new-value)))
            (else
             (error "Unexpeccted params--"
                    n))))))


(rand 'generate)
(rand 'generate)
(rand 'generate)
(rand 'generate)
(rand 'generate)

((rand 'reset) 0)

(rand 'generate)
(rand 'generate)
(rand 'generate)
(rand 'generate)
(rand 'generate)