21 lines
399 B
Scheme
21 lines
399 B
Scheme
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;;
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;; The prime-stream example [SICP 2ed. p. 327]
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;;
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(load "stream.scm")
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(define (divisible? x y) (= (remainder x y) 0))
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(define (sieve stream)
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(cons-stream
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(stream-car stream)
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(sieve (stream-filter
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(lambda (x)
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(not (divisible? x (stream-car stream))))
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(stream-cdr stream)))))
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(define primes (sieve (integers-starting-from 2)))
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(display (stream-ref primes 300))
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(newline)
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