1 (define (factorial n)
2   (if (= n 1)
3       1
4       (* n (factorial (- n 1)))))
5 
6 (define (factorial n)
7   (fact-iter 1 1 n))
8 (define (fact-iter product counter max-count)
9   (if (> counter max-count)
10       product
11       (fact-iter (* product counter) (+ counter 1) max-count)))