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题库练习 Average Numbers

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A8300 | $Average Numbers$

时间限制1s

内存限制256MB

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题目描述

You are given a sequence of positive integers $a_{1},a_{2},...,a_{n}$ . Find all such indices $i$ , that the $i$ -th element equals the arithmetic mean of all other elements (that is all elements except for this one).

输入格式

The first line contains the integer $n$ ( $2<=n<=2·10^{5}$ ). The second line contains elements of the sequence $a_{1},a_{2},...,a_{n}$ ( $1<=a_{i}<=1000$ ). All the elements are positive integers.

输出格式

Print on the first line the number of the sought indices. Print on the second line the sought indices in the increasing order. All indices are integers from $1$ to $n$ . If the sought elements do not exist, then the first output line should contain number $0$ . In this case you may either not print the second line or print an empty line.

输入输出样例

输入 #1

5
1 2 3 4 5

输出 #1

1
3

输入 #2

4
50 50 50 50

输出 #2

4
1 2 3 4

C++ 编辑器

输入

输出