SICP Exercise 3.9 factorial environment structures

Exercise 3.9.  In section 1.2.1 we used the substitution model to analyze two procedures for computing factorials, a recursive version

(define (factorial n)
  (if (= n 1)
      1
      (* n (factorial (- n 1)))))

and an iterative version

(define (factorial n)
  (fact-iter 1 1 n))
(define (fact-iter product counter max-count)
  (if (> counter max-count)
      product
      (fact-iter (* counter product)
                 (+ counter 1)
                 max-count)))

Show the environment structures created by evaluating (factorial 6) using each version of the factorial procedure.14

SOLUTION




The worked out sheets are here:

 Page 1
Page 2
Page 3

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