我可以让过滤器工作,但它不会破坏性地做到这一点。以下是起始代码和测试用例:
(define (filter! f s)
;;Your solution
测试用例:
(define (big x) (> x 5))
(define ints (list 1 10 3 8 4 7))
(define ints1 (cdr ints))
(define filtered-ints (filter! big ints))
filtered-ints
; expect (10 8 7)
(eq? filtered-ints ints1) ; expect #t
有人可以帮忙吗?