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17 lines
557 B
17 lines
557 B
2 years ago
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Exercise 4.37: Ben Bitdiddle claims that the
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following method for generating Pythagorean triples is more efficient than the
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one in Exercise 4.35. Is he correct? (Hint: Consider the number of
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possibilities that must be explored.)
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(define (a-pythagorean-triple-between low high)
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(let ((i (an-integer-between low high))
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(hsq (* high high)))
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(let ((j (an-integer-between i high)))
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(let ((ksq (+ (* i i) (* j j))))
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(require (>= hsq ksq))
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(let ((k (sqrt ksq)))
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(require (integer? k))
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(list i j k))))))
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