22 lines
472 B
Racket
22 lines
472 B
Racket
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(define (square n)
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(* n n))
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(define (smallest-divisor n)
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(find-divisor n 2))
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(define (find-divisor n test-divisor)
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(define (next iterator)
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(if (= iterator 2) 3 (+ iterator 2)))
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(cond ((> (square test-divisor) n) n)
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((divides? test-divisor n) test-divisor)
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(else (find-divisor n (next test-divisor)))))
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; find-divisor
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(define (divides? a b)
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(= (remainder b a) 0))
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(smallest-divisor 199)
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(smallest-divisor 1999)
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(smallest-divisor 19999)
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