(define (cc) (let ((count 0)) (list
  (lambda () (set! count (+ count 1)))
  (lambda () count))))

; Demos
(define c1 (cc))
(define i1 (car c1))
(define r1 (cadr c1))

(define c2 (cc))
(define i2 (car c2))
(define r2 (cadr c2))

(list (r1) (r2)) ; => (0 0)
(begin (i2) (i1) (i2))
(list (r1) (r2)) ; => (1 2)