35 lines
881 B
Scheme
35 lines
881 B
Scheme
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;;; PRIMES -- Compute primes less than 100, written by Eric Mohr.
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(define (interval-list m n)
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(if (> m n)
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'()
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(cons m (interval-list (+ 1 m) n))))
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(define (sieve l)
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(letrec ((remove-multiples
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(lambda (n l)
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(if (null? l)
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'()
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(if (= (modulo (car l) n) 0)
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(remove-multiples n (cdr l))
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(cons (car l)
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(remove-multiples n (cdr l))))))))
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(if (null? l)
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'()
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(cons (car l)
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(sieve (remove-multiples (car l) (cdr l)))))))
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(define (primes<= n)
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(sieve (interval-list 2 n)))
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(define (main)
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(run-benchmark
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"primes"
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primes-iters
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(lambda (result)
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(equal? result
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'(2 3 5 7 11 13 17 19 23 29 31 37 41
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43 47 53 59 61 67 71 73 79 83 89 97)))
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(lambda (n) (lambda () (primes<= n)))
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100))
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