path: root/js/games/nluqo.github.io/~bh/61a-pages/Lectures/3.5/sieve.scm



(define (divisible? x y) (= (remainder x y) 0))

(define (sieve stream)
  (cons-stream
   (stream-car stream)
   (sieve (stream-filter
	   (lambda (x) (not (divisible? x (stream-car stream))))
	   (stream-cdr stream)))))

(define primes (sieve (stream-cdr integers)))
(define (divisible? x y) (= (remainder x y) 0))

(define (sieve stream)
  (cons-stream
   (stream-car stream)
   (sieve (stream-filter
	   (lambda (x) (not (divisible? x (stream-car stream))))
	   (stream-cdr stream)))))

(define primes (sieve (stream-cdr integers)))