CF1741B.Funny Permutation

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题目描述

A sequence of nn numbers is called permutation if it contains all numbers from 11 to nn exactly once. For example, the sequences [3,1,4,2][3, 1, 4, 2] , [ 11 ] and [2,1][2,1] are permutations, but [1,2,1][1,2,1] , [0,1][0,1] and [1,3,4][1,3,4] are not.

For a given number nn you need to make a permutation pp such that two requirements are satisfied at the same time:

  • For each element pip_i , at least one of its neighbors has a value that differs from the value of pip_i by one. That is, for each element pip_i ( 1in1 \le i \le n ), at least one of its neighboring elements (standing to the left or right of pip_i ) must be pi+1p_i + 1 , or pi1p_i - 1 .
  • the permutation must have no fixed points. That is, for every ii ( 1in1 \le i \le n ), piip_i \neq i must be satisfied.

Let's call the permutation that satisfies these requirements funny.

For example, let n=4n = 4 . Then [ 4,3,1,24, 3, 1, 2 ] is a funny permutation, since:

  • to the right of p1=4p_1=4 is p2=p11=41=3p_2=p_1-1=4-1=3 ;
  • to the left of p2=3p_2=3 is p1=p2+1=3+1=4p_1=p_2+1=3+1=4 ;
  • to the right of p3=1p_3=1 is p4=p3+1=1+1=2p_4=p_3+1=1+1=2 ;
  • to the left of p4=2p_4=2 is p3=p41=21=1p_3=p_4-1=2-1=1 .
  • for all ii is piip_i \ne i .

For a given positive integer nn , output any funny permutation of length nn , or output -1 if funny permutation of length nn does not exist.

输入格式

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

The description of the test cases follows.

Each test case consists of f single line containing one integer nn ( 2n21052 \le n \le 2 \cdot 10^5 ).

It is guaranteed that the sum of nn over all test cases does not exceed 21052 \cdot 10^5 .

输出格式

For each test case, print on a separate line:

  • any funny permutation pp of length nn ;
  • or the number -1 if the permutation you are looking for does not exist.

输入输出样例

  • 输入#1

    5
    4
    3
    7
    5
    2

    输出#1

    3 4 2 1
    -1
    6 7 4 5 3 2 1
    5 4 1 2 3
    2 1

说明/提示

The first test case is explained in the problem statement.

In the second test case, it is not possible to make the required permutation: permutations [1,2,3][1, 2, 3] , [1,3,2][1, 3, 2] , [2,1,3][2, 1, 3] , [3,2,1][3, 2, 1] have fixed points, and in [2,3,1][2, 3, 1] and [3,1,2][3, 1, 2] the first condition is met not for all positions.

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