AtCoder Grand Contest 001
D
Arrays and Palindrome
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原题
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Problem Statement

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Snuke got a present from his mother on his birthday. The present was a pair of two sequences $a$ and $b$, consisting of positive integers. They satisfied all of the following properties:

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  • The sum of all elements of $a$ is $N$.
  • The sum of all elements of $b$ is $N$.
  • Any string of length $N$ that satisfies the following two conditions (1) and (2) will also satisfy the condition (3).
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He was happy, until one day he lost both of the sequences. Now, he only remembers that the sequence $a$ was a permutation of another sequence $A$ of length $M$.

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To bring him happiness again, his mother has decided to give him another pair of sequences $a$ and $b$ that satisfies his favorite properties and is consistent with his memory.

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Constraints

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  • $1≦N≦10^5$
  • $1≦M≦100$
  • $1≦A_i≦10^5$
  • The sum of all $A_i$ equals $N$.
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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 M
A_1 A_2 ... A_M

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Output

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If there exists a pair of sequences $a$ and $b$ that satisfies the properties and is consistent with Snuke's memory, print three lines. The first line must contain the sequence $a$, the second line must contain the length of the sequence $b$, and the third line must contain the sequence $b$.

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If such a pair does not exist (because Snuke's memory is wrong or some other reason), print a single line containing the word Impossible (case-sensitive).

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样例

Input #1
3 2
2 1
Output #1
1 2
1
3
Input #2
6 1
6
Output #2
6
3
1 2 3
Input #3
55 10
1 2 3 4 5 6 7 8 9 10
Output #3
Impossible
题目信息
题号
agc001_d
时间限制
2 s
内存限制
256 MB

题面与样例版权归 AtCoder 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。