Scheme 方案Rswap功能

有人能帮我完成这个功能吗

使用类似于swap递归版本的scheme函数

(reswap '((h i)（j k) l (m n o)))

应该回来

((k j) (i h) (n m o) l) ;

及

应该回来

(c (b a) g ((f e) d) (i h))) 

---

哈哈，这看起来是个好问题，但我得到的只是

(define (swap lst)
    ; if the list is empty or has a single element
    (cond ((or (null? lst) (null? (cdr lst)))
    ; then return that list
     lst)
    (else
    ; by first adding the second element
     (cons (cadr lst)
           (cons (car lst)
                 (swap (cddr lst)))))))

但这只是正常的交换

试试这个：

(define (rswap lst)

  ;; Create a helper function to do the recursive work.
  (define (helper in out)

    ;; If the input is not a list, simply return it.
    ;; There is nothing to be done to rswap it.
    (if (not (list? in))
      in

      ;; If in is an empty list, simply return the out.
      (if (null? in)
        out

        ;; If in is a list with only one item, append
        ;; the result of calling rswap on the item to 
        ;; out and return it.
        (if (null? (cdr in))
          (append out (list (rswap (car in))))

          ;; This is where the recursion continues.
          ;; Take two items off in before the next call.
          ;; rswap the two items and add them to out.
          (helper
            (cddr in)
            (append out (list (rswap (cadr in)) (rswap (car in)))))))))

  (helper lst '()))

---

你试过什么吗？如果是的话，请展示你试过的。你能看一下吗？（DEFINE（rswap lst）（COND（（or）（NULL？lst）（NULL？（CDR lst）））lst）；如果列表为空或单个元素，则将返回该列表（否则（CONS（CONS（CONS（CDR（CAR（CDR lst））））（CAR（CAR（CDR lst）））（CONS（CDR（CAR lst））（C$；获取第二个元素，然后添加第一个元素（rswap（CDDR lst））））））

(define (rswap lst)

  ;; Create a helper function to do the recursive work.
  (define (helper in out)

    ;; If the input is not a list, simply return it.
    ;; There is nothing to be done to rswap it.
    (if (not (list? in))
      in

      ;; If in is an empty list, simply return the out.
      (if (null? in)
        out

        ;; If in is a list with only one item, append
        ;; the result of calling rswap on the item to 
        ;; out and return it.
        (if (null? (cdr in))
          (append out (list (rswap (car in))))

          ;; This is where the recursion continues.
          ;; Take two items off in before the next call.
          ;; rswap the two items and add them to out.
          (helper
            (cddr in)
            (append out (list (rswap (cadr in)) (rswap (car in)))))))))

  (helper lst '()))