sal2's blog

I need a hint
By sal2, history, 6 years ago, In English

Can anyone give me a hint to solve this problem https://codeforces.net/contest/1152/problem/C please? Thank you

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6 years ago, # |
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try to make gcd as large as possible; gcd(a,b)=gcd(b-a,a)

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6 years ago, # |
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hint 1
hint 2
hint 3
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    6 years ago, # ^ |
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    one more hint?

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      6 years ago, # ^ |
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      d is a divisor of a + k, so there is a integer n that a + k = n * d. Therefore, k = n * d — a. We also want k to be as small as possible, so n should be as small as possible.

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