311054: CF1927E. Klever Permutation

You are given two integers $n$ and $k$ ($k \le n$), where $k$ is even.

A permutation of length $n$ is an array consisting of $n$ distinct integers from $1$ to $n$ in any order. For example, $[2,3,1,5,4]$ is a permutation, but $[1,2,2]$ is not a permutation (as $2$ appears twice in the array) and $[0,1,2]$ is also not a permutation (as $n=3$, but $3$ is not present in the array).

Your task is to construct a $k$-level permutation of length $n$.

A permutation is called $k$-level if, among all the sums of continuous segments of length $k$ (of which there are exactly $n - k + 1$), any two sums differ by no more than $1$.

More formally, to determine if the permutation $p$ is $k$-level, first construct an array $s$ of length $n - k + 1$, where $s_i=\sum_{j=i}^{i+k-1} p_j$, i.e., the $i$-th element is equal to the sum of $p_i, p_{i+1}, \dots, p_{i+k-1}$.

A permutation is called $k$-level if $\max(s) - \min(s) \le 1$.

Find any $k$-level permutation of length $n$.

The first line of the input contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases. This is followed by the description of the test cases.

The first and only line of each test case contains two integers $n$ and $k$ ($2 \le k \le n \le 2 \cdot 10^5$, $k$ is even), where $n$ is the length of the desired permutation.

It is guaranteed that the sum of $n$ for all test cases does not exceed $2 \cdot 10^5$.

For each test case, output any $k$-level permutation of length $n$.

It is guaranteed that such a permutation always exists given the constraints.

5
2 2
3 2
10 4
13 4
7 4

2 1
1 3 2
1 8 4 10 2 7 5 9 3 6
4 10 1 13 5 9 2 12 6 8 3 11 7
1 6 3 7 2 5 4

In the second test case of the example:

• $p_1 + p_2 = 3 + 1 = 4$;
• $p_2 + p_3 = 1 + 2 = 3$.