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CF1701B.Permutation
Permutation
Recall that a permutation of length is an array where each element from to occurs exactly once.
For a fixed positive integer , let's define the cost of the permutation of length as the number of indices such that .
For example, if and , then the cost of such a permutation is , because and .
Your task is the following one: for a given value , find the permutation of length and the value with maximum possible cost (over all ways to choose the permutation and ). If there are multiple answers, then print any of them.
Input
The first line contains a single integer () — the number of test cases.
The single line of each test case contains a single integer ().
The sum of over all test cases does not exceed .
Output
For each test case, print the value in the first line, and integers in the second line — the permutation itself. If there are multiple answers, then print any of them.
Samples
2
2
3
2
1 2
3
2 1 3
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