CF1858C.Yet Another Permutation Problem

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题目描述

Alex got a new game called "GCD permutations" as a birthday present. Each round of this game proceeds as follows:

  • First, Alex chooses a permutation ^{\dagger} a1,a2,,ana_1, a_2, \ldots, a_n of integers from 11 to nn .
  • Then, for each ii from 11 to nn , an integer di=gcd(ai,a(imodn)+1)d_i = \gcd(a_i, a_{(i \bmod n) + 1}) is calculated.
  • The score of the round is the number of distinct numbers among d1,d2,,dnd_1, d_2, \ldots, d_n .

Alex has already played several rounds so he decided to find a permutation a1,a2,,ana_1, a_2, \ldots, a_n such that its score is as large as possible.

Recall that gcd(x,y)\gcd(x, y) denotes the greatest common divisor (GCD) of numbers xx and yy , and xmodyx \bmod y denotes the remainder of dividing xx by yy .

^{\dagger} A permutation of length nn is an array consisting of nn distinct integers from 11 to nn in arbitrary order. For example, [2,3,1,5,4][2,3,1,5,4] is a permutation, but [1,2,2][1,2,2] is not a permutation ( 22 appears twice in the array), and [1,3,4][1,3,4] is also not a permutation ( n=3n=3 but there is 44 in the array).

输入格式

The first line of the input contains a single integer tt ( 1t1041 \le t \le 10^4 ) — the number of test cases.

Each test case consists of one line containing a single integer nn ( 2n1052 \le n \le 10^5 ).

It is guaranteed that the sum of nn over all test cases does not exceed 10510^5 .

输出格式

For each test case print nn distinct integers a1,a2,,ana_{1},a_{2},\ldots,a_{n} ( 1ain1 \le a_i \le n ) — the permutation with the largest possible score.

If there are several permutations with the maximum possible score, you can print any one of them.

输入输出样例

  • 输入#1

    4
    5
    2
    7
    10

    输出#1

    1 2 4 3 5 
    1 2 
    1 2 3 6 4 5 7 
    1 2 3 4 8 5 10 6 9 7

说明/提示

In the first test case, Alex wants to find a permutation of integers from 11 to 55 . For the permutation a=[1,2,4,3,5]a=[1,2,4,3,5] , the array dd is equal to [1,2,1,1,1][1,2,1,1,1] . It contains 22 distinct integers. It can be shown that there is no permutation of length 55 with a higher score.

In the second test case, Alex wants to find a permutation of integers from 11 to 22 . There are only two such permutations: a=[1,2]a=[1,2] and a=[2,1]a=[2,1] . In both cases, the array dd is equal to [1,1][1,1] , so both permutations are correct.

In the third test case, Alex wants to find a permutation of integers from 11 to 77 . For the permutation a=[1,2,3,6,4,5,7]a=[1,2,3,6,4,5,7] , the array dd is equal to [1,1,3,2,1,1,1][1,1,3,2,1,1,1] . It contains 33 distinct integers so its score is equal to 33 . It can be shown that there is no permutation of integers from 11 to 77 with a score higher than 33 .

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