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B. Points and Minimum Distance

time limit per test

2 secondsmemory limit per test

512 megabytesinput

standard inputoutput

standard outputYou are given a sequence of integers $$$a$$$ of length $$$2n$$$. You have to split these $$$2n$$$ integers into $$$n$$$ pairs; each pair will represent the coordinates of a point on a plane. Each number from the sequence $$$a$$$ should become the $$$x$$$ or $$$y$$$ coordinate of exactly one point. Note that some points can be equal.

After the points are formed, you have to choose a path $$$s$$$ that starts from one of these points, ends at one of these points, and visits all $$$n$$$ points at least once.

The length of path $$$s$$$ is the sum of distances between all adjacent points on the path. In this problem, the distance between two points $$$(x_1, y_1)$$$ and $$$(x_2, y_2)$$$ is defined as $$$|x_1-x_2| + |y_1-y_2|$$$.

Your task is to form $$$n$$$ points and choose a path $$$s$$$ in such a way that the length of path $$$s$$$ is minimized.

Input

The first line contains a single integer $$$t$$$ ($$$1 \le t \le 100$$$) — the number of testcases.

The first line of each testcase contains a single integer $$$n$$$ ($$$2 \le n \le 100$$$) — the number of points to be formed.

The next line contains $$$2n$$$ integers $$$a_1, a_2, \dots, a_{2n}$$$ ($$$0 \le a_i \le 1\,000$$$) — the description of the sequence $$$a$$$.

Output

For each testcase, print the minimum possible length of path $$$s$$$ in the first line.

In the $$$i$$$-th of the following $$$n$$$ lines, print two integers $$$x_i$$$ and $$$y_i$$$ — the coordinates of the point that needs to be visited at the $$$i$$$-th position.

If there are multiple answers, print any of them.

Example

Input

2215 1 10 5310 30 20 20 30 10

Output

9 10 1 15 5 20 20 20 10 30 10 30

Note

In the first testcase, for instance, you can form points $$$(10, 1)$$$ and $$$(15, 5)$$$ and start the path $$$s$$$ from the first point and end it at the second point. Then the length of the path will be $$$|10 - 15| + |1 - 5| = 5 + 4 = 9$$$.

In the second testcase, you can form points $$$(20, 20)$$$, $$$(10, 30)$$$, and $$$(10, 30)$$$, and visit them in that exact order. Then the length of the path will be $$$|20 - 10| + |20 - 30| + |10 - 10| + |30 - 30| = 10 + 10 + 0 + 0 = 20$$$.

Codeforces (c) Copyright 2010-2023 Mike Mirzayanov

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