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29 lines
624 B
29 lines
624 B
2 years ago
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Exercise 3.9: In 1.2.1 we used the
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substitution model to analyze two procedures for computing factorials, a
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recursive version
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(define (factorial n)
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(if (= n 1)
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1
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(* n (factorial (- n 1)))))
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and an iterative version
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(define (factorial n)
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(fact-iter 1 1 n))
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(define (fact-iter product
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counter
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max-count)
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(if (> counter max-count)
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product
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(fact-iter (* counter product)
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(+ counter 1)
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max-count)))
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Show the environment structures created by evaluating (factorial 6)
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using each version of the factorial procedure.142
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