(define (accumulate op initial sequence)

  (if (null? sequence)

      initial

      (op (car sequence)

          (accumulate op initial (cdr sequence)))))

(define fold-right accumulate)

(define (fold-left op initial sequence)

  (define (iter result rest)

    (if (null? rest)

        result

        (iter (op result (car rest))

              (cdr rest))))

  (iter initial sequence))
(define nil (list))
(define (reverse_ sequence)

  (fold-right solution nil sequence))
(define (reverse_2 sequence)

  (fold-left solution2 nil sequence))
(define solution (lambda (x y) (append y (list x))))

(define solution2 (lambda (x y) (cons y x)))
'test result

> (reverse (list 1 2 3 4 5))

(5 4 3 2 1)

> (reverse_ (list 1 2 3 4 5))

(5 4 3 2 1)

> (reverse_2 (list 1 2 3 4 5))

(5 4 3 2 1)

>