15 lines
300 B
Scheme
15 lines
300 B
Scheme
#lang sicp
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(define (make-interval a b) (cons a b))
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(define (lower-bound i)
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(car i))
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(define (upper-bound i)
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(cdr i))
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(define (sub-interval a b)
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(make-interval (- (lower-bound a)
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(upper-bound b))
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(- (upper-bound a)
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(lower-bound b))))
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