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49 lines
708 B
49 lines
708 B
2 years ago
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Exercise 4.35: Write a procedure
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an-integer-between that returns an integer between two given bounds.
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This can be used to implement a procedure that finds Pythagorean triples, i.e.,
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triples of integers
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(
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i
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,
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j
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,
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k
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)
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between the given bounds such that
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i
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≤
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j
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and
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i
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2
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+
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j
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2
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=
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k
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2
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, as follows:
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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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(let ((j (an-integer-between i high)))
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(let ((k (an-integer-between j high)))
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(require (= (+ (* i i) (* j j))
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(* k k)))
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(list i j k)))))
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