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CF2218C.The 67th Permutation Problem
The 67th Permutation Problem
Upon arriving at school, Macaque was rather brusquely greeted by his friend, AG-88301, the latter having skived off his homework due to spending the entire night yapping to an unsuspecting stranger about his groundbreaking work on a proof of the Collatz conjecture and his -th unreciprocated love interest. So, as had become customary, AG-88301, with ever decreasing levels of gratitude or appreciation, made Macaque do his homework for him. At this point, Macaque had had enough, and turned to his minions (you guys!) to solve AG-88301's homework task.
You are given an integer . You must construct a permutation of length such that, if you partition the permutation into contiguous blocks with elements, the sum of the medians of these blocks is maximised.
More formally, you must construct a permutation of length such that $um_{i=0}^{n-1}\operatorname{median}(a_{3i+1},a_{3i+2},a_{3i+3})$ is maximised. If there are multiple possible , output any.
A permutation of length is an array consisting of distinct integers from to in arbitrary order. For example, is a permutation, but is not a permutation ( appears twice in the array), and is also not a permutation ( but there is in the array).
The median of an array containing elements is the -nd element after is sorted in non-decreasing order.
Input
Each test contains multiple test cases. The first line contains the number of test cases (). The description of the test cases follows.
The first and only line of each test case contains an integer ().
It is guaranteed that the sum of does not exceed over all test cases.
Output
For each test case, output a permutation such that the sum of the medians of the contiguous blocks is maximised. If there are multiple possible , output any.
Note
In the first test case, is a possible answer because $\operatorname{median}(1,3,4) + \operatorname{median}(2,5,6) = 3+5 = 8$, and it can be shown that is the maximal possible sum of medians.
In the second test case, is a possible answer because the only achievable sum of medians when is .
Samples
3
2
1
3
1 3 4 2 5 6
3 1 2
5 2 4 8 3 9 7 1 6
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