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수학동아 - 폴리매스
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[잡담] 어려운 문제
muse 2019.11.14 06:31 조회 527
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페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

너무 어렵나요...ㅠㅠ

 

어려운 문제 1 힌트 드립니다.

a가 b의 약수이면 (b/a)도 b의 약수입니다.

 

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  •  
    21세기오일러 Lv.11 2019.11.14 06:43

    왜냐하면 a곱하기 a분의 b는 b이기 때문입니다. 즉, n의 약수를 구하려면 n의 제곱근까지만 나눠보면 된다는 뜻이죠. 그런데 여기까지는 알겠는데 저는 못풀겠어요.

    댓글 작성하기 좋아요0 댓글수3
    •  
      muse Lv.6 2019.11.14 06:49

      이렇게 하면 프로그램을 3번 문제의 경우 약 1000배 빠르게 할 수 있습니다.

      따라서 답은 약 10초 안에 나온다는 것이죠.

      좋아요0
    •  
      21세기오일러 Lv.11 2019.11.14 06:53

      프로그램을 짤 시간이 없어서...

      좋아요0
    •  
      muse Lv.6 2019.11.14 07:13

      괜찮아요 ^^

       

      좋아요0
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