SICP 习题2.39 reverse实现

(define reverse-list 
  (lambda (s)
    (if (null? s)
      '()
      (append (reverse-list (cdr s)) (list (car s))))))

(newline)
(display (reverse-list '(1 2 3 4))) 

(newline)
(display (reverse '(1 2 3 4)))

(define (reverse sequence)
  (fold-right (lambda (x y) (append y (list x))) '() sequence))

(newline)
(display (reverse '(1 2 3 4)))

(define (reverse sequence)
  (fold-left  (lambda (x y) (append (list y) x)) '() sequence))

(newline)
(display (reverse '(1 2 3 4)))