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CF1942A.Farmer John's Challenge
Farmer John's Challenge
Let's call an array sorted if .
You are given two of Farmer John's favorite integers, and . He challenges you to find any array satisfying the following requirements:
- for each ;
- Out of the total cyclic shifts of , exactly of them are sorted.
If there is no such array , output .
The -th () cyclic shift of the array is . If denotes the 'th element of the 'th cyclic shift of , exactly such should satisfy $c_{x,1} \leq c_{x,2} \leq \ldots \leq c_{x, n - 1} \leq c_{x, n}$.
For example, the cyclic shifts for are the following:
- : (sorted);
- : (not sorted);
- : (not sorted);
- : (not sorted).
Input
The first line contains () — the number of test cases.
Each test case contains two integers and () — the length of and the number of sorted cyclic shifts must have.
It is guaranteed that the sum of over all test cases does not exceed .
Output
For each test case, print a single line:
- if there is a valid array , output integers, representing ;
- otherwise, output .
If there are multiple solutions, print any of them.
Note
In the first testcase, satisfies :
The two cyclic shifts of are and , which are both and are sorted.
In the second testcase, satisfies :
The three cyclic shifts of are , , , which are , , and , respectively.
Only is sorted.
Samples
3
2 2
3 1
3 2
1 1
69420 69 420
-1
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