Problem E

Statement
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Description:
Define the simple skewness of a collection of numbers to be the collection's mean minus its median. You are given a list of n (not necessarily distinct) integers. Find the non-empty subset (with repetition) with the maximum simple skewness.

The mean of a collection is the average of its elements. The median of a collection is its middle element when all of its elements are sorted, or the average of its two middle elements if it has even size.

Input Format:
The first line of the input contains a single integer n (1 ≤ n ≤ 200 000) — the number of elements in the list.

The second line contains n integers xi (0 ≤ xi ≤ 1 000 000) — the ith element of the list.

Output Format:
In the first line, print a single integer k — the size of the subset.

In the second line, print k integers — the elements of the subset in any order.

If there are multiple optimal subsets, print any.

Note:
In the first case, the optimal subset is $${ \{ 1, 2, 1 2 \} }$$, which has mean 5, median 2, and simple skewness of 5 - 2 = 3.

In the second case, the optimal subset is $${ \{ 1, 1, 2 \} }$$. Note that repetition is allowed.

In the last case, any subset has the same median and mean, so all have simple skewness of 0.