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#lang racket
(require "../../shared/lists.rkt")

(define (fold-right op initial sequence)
  (accumulate op initial sequence))

(define (fold-left op initial sequence)
  (define (iter result rest)
    (if (null? rest)
      result
      (iter (op result (car rest))
            (cdr rest))))
  (iter initial sequence))

((lambda ()
   (newline)
   (display (fold-right / 1 (list 1 2 3)))
   (newline)
   (display (fold-left / 1 (list 1 2 3)))
   (newline)
   (display (fold-right list '() (list 1 2 3)))
   (newline)
   (display (fold-left list '() (list 1 2 3)))))