There is an integer sequence $a$ of length $n$, where each element is initially $-1$.
Misuki has two typewriters where the first one writes letters from left to right, with a pointer initially pointing to $1$, and another writes letters from right to left with a pointer initially pointing to $n$.
Misuki would choose one of the typewriters and use it to perform the following operations until $a$ becomes a permutation of $[1, 2, \ldots, n]$
- write number: write the minimum positive integer that isn't present in the array
$a$to the element$a_i$,$i$is the position where the pointer points at. Such operation can be performed only when$a_i = -1$. - carriage return: return the pointer to its initial position (i.e.
$1$for the first typewriter,$n$for the second) - move pointer: move the pointer to the next position, let
$i$be the position the pointer points at before this operation, if Misuki is using the first typewriter,$i := i + 1$would happen, and$i := i - 1$otherwise. Such operation can be performed only if after the operation,$1 \le i \le n$holds.
Your task is to construct any permutation $p$ of length $n$, such that the minimum number of carriage return operations needed to make $a = p$ is the same no matter which typewriter Misuki is using.
Input
Each test contains multiple test cases. The first line of input contains a single integer $t$ ($1 \le t \le 500$) — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single integer $n$ ($1 \le n \le 2 \cdot 10^5$) — the length of the permutation.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
Output
For each test case, output a line of $n$ integers, representing the permutation $p$ of length $n$ such that the minimum number of carriage return operations needed to make $a = p$ is the same no matter which typewriter Misuki is using, or $-1$ if it is impossible to do so.
If there are multiple valid permutations, you can output any of them.
Note
In the first testcase, it's possible to make $a = p = [1]$ using $0$ carriage return operations.
In the second testcase, it is possible to make $a = p = [1, 2]$ with the minimal number of carriage returns as follows:
If Misuki is using the first typewriter:
- Write number: write
$1$to$a_1$,$a$becomes$[1, -1]$ - Move pointer: move the pointer to the next position. (i.e.
$2$) - Write number: write
$2$to$a_2$,$a$becomes$[1, 2]$
If Misuki is using the second typewriter:
- Move pointer: move the pointer to the next position. (i.e.
$1$) - Write number: write
$1$to$a_1$,$a$becomes$[1, -1]$ - Carriage return: return the pointer to
$2$. - Write number: write
$2$to$a_2$,$a$becomes$[1, 2]$
It can be proven that the minimum number of carriage returns needed to transform $a$ into $p$ when using the first typewriter is $0$ and it is $1$ when using the second one, so this permutation is not valid.
Similarly, $p = [2, 1]$ is also not valid, so there is no solution for $n = 2$.
In the third testcase, it is possibile to make $a = p = [3, 1, 2]$ with $1$ carriage return with both the first and the second typewriter. It can be proven that, for both typewriters, it is impossible to write $p$ with $0$ carriage returns.
With the first typewriter it is possible to:
- Move pointer: move the pointer to the next position. (i.e.
$2$) - Write number: write
$1$to$a_2$,$a$becomes$[-1, 1, -1]$ - Move pointer: move the pointer to the next position. (i.e.
$3$) - Write number: write
$2$to$a_3$,$a$becomes$[-1, 1, 2]$ - Carriage return: return the pointer to
$1$. - Write number: write
$3$to$a_1$,$a$becomes$[3,1,2]$
With the second typewriter it is possible to:
- Move pointer: move the pointer to the next position. (i.e.
$2$) - Write number: write
$1$to$a_2$,$a$becomes$[-1, 1, -1]$ - Carriage return: return the pointer to
$3$. - Write number: write
$2$to$a_3$,$a$becomes$[-1, 1, 2]$ - Move pointer: move the pointer to the next position. (i.e.
$2$) - Move pointer: move the pointer to the next position. (i.e.
$1$) - Write number: write
$3$to$a_1$,$a$becomes$[3, 1, 2]$
样例
3
1
2
3
1
-1
3 1 2
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