Codeforces Round 716 (Div. 2)
C
Product 1 Modulo N
Codeforces
1600
原题
← BD →
翻译中…

Now you get Baby Ehab's first words: "Given an integer $n$, find the longest subsequence of $[1,2, \ldots, n-1]$ whose product is $1$ modulo $n$." Please solve the problem.

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A sequence $b$ is a subsequence of an array $a$ if $b$ can be obtained from $a$ by deleting some (possibly all) elements. The product of an empty subsequence is equal to $1$.

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Input

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The only line contains the integer $n$ ($2 \le n \le 10^5$).

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Output

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The first line should contain a single integer, the length of the longest subsequence.

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The second line should contain the elements of the subsequence, in increasing order.

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If there are multiple solutions, you can print any.

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Note

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In the first example, the product of the elements is $6$ which is congruent to $1$ modulo $5$. The only longer subsequence is $[1,2,3,4]$. Its product is $24$ which is congruent to $4$ modulo $5$. Hence, the answer is $[1,2,3]$.

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样例

Input #1
5
Output #1
3
1 2 3
InputCopy OutputCopy
Input #2
8
Output #2
4
1 3 5 7
InputCopy OutputCopy
题目信息
题号
1514C
时间限制
1 s
内存限制
256 MB
标签
贪心
数论

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