AtCoder Regular Contest 198 (Div. 2)
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Problem Statement

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You are given a positive integer $N$. A set $S$ of positive integers between $1$ and $N$ (inclusive) is called a good set if it satisfies the following condition:

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  • For every pair of elements $x$ and $y$ in $S$, the remainder when $x$ is divided by $y$ is not $1$.
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Construct one good set with the maximum possible number of elements.

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Constraints

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  • $1 \le N \le 2 \times 10^{5}$
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Input

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The input is given from Standard Input in the following format:

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N

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Output

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Let $k$ be the number of elements of the good set $S$ you constructed, and let $S = \lbrace S_1,S_2,\dots,S_k \rbrace$ be its elements. Output in the following format:

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k
S_1\ S_2\ \dots\ S_k

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If multiple solutions exist, any of them will be accepted.

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样例

Input #1
5
Output #1
2
3 5
For example, $\lbrace 3,5 \rbrace$ and $\lbrace 2 \rbrace$ are good sets. On the other hand, $\lbrace 2,3,5 \rbrace$ and $\lbrace 1,2,3,4,5 \rbrace$ are not good sets. No good set with three or more elements exists, so $\lbrace 3,5 \rbrace$ is one of the good sets with the maximum number of elements.
Input #2
2
Output #2
1
2
题目信息
题号
arc198_a
时间限制
2 s
内存限制
1024 MB

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