An identity permutation of length $n$ is an array $[1, 2, 3, \dots, n]$.
We performed the following operations to an identity permutation of length $n$:
- firstly, we cyclically shifted it to the right by
$k$positions, where$k$is unknown to you (the only thing you know is that$0 \le k \le n - 1$). When an array is cyclically shifted to the right by$k$positions, the resulting array is formed by taking$k$last elements of the original array (without changing their relative order), and then appending$n - k$first elements to the right of them (without changing relative order of the first$n - k$elements as well). For example, if we cyclically shift the identity permutation of length$6$by$2$positions, we get the array$[5, 6, 1, 2, 3, 4]$; - secondly, we performed the following operation at most
$m$times: pick any two elements of the array and swap them.
You are given the values of $n$ and $m$, and the resulting array. Your task is to find all possible values of $k$ in the cyclic shift operation.
Input
The first line contains one integer $t$ ($1 \le t \le 10^5$) — the number of test cases.
Each test case consists of two lines. The first line contains two integers $n$ and $m$ ($3 \le n \le 3 \cdot 10^5$; $0 \le m \le \frac{n}{3}$).
The second line contains $n$ integers $p_1, p_2, \dots, p_n$ ($1 \le p_i \le n$, each integer from $1$ to $n$ appears in this sequence exactly once) — the resulting array.
The sum of $n$ over all test cases does not exceed $3 \cdot 10^5$.
Output
For each test case, print the answer in the following way:
- firstly, print one integer
$r$($0 \le r \le n$) — the number of possible values of$k$for the cyclic shift operation; - secondly, print
$r$integers$k_1, k_2, \dots, k_r$($0 \le k_i \le n - 1$) — all possible values of$k$in increasing order.
Note
Consider the example:
- in the first test case, the only possible value for the cyclic shift is
$3$. If we shift$[1, 2, 3, 4]$by$3$positions, we get$[2, 3, 4, 1]$. Then we can swap the$3$-rd and the$4$-th elements to get the array$[2, 3, 1, 4]$; - in the second test case, the only possible value for the cyclic shift is
$0$. If we shift$[1, 2, 3]$by$0$positions, we get$[1, 2, 3]$. Then we don't change the array at all (we stated that we made at most$1$swap), so the resulting array stays$[1, 2, 3]$; - in the third test case, all values from
$0$to$2$are possible for the cyclic shift: - if we shift
$[1, 2, 3]$by$0$positions, we get$[1, 2, 3]$. Then we can swap the$1$-st and the$3$-rd elements to get$[3, 2, 1]$;- if we shift
$[1, 2, 3]$by$1$position, we get$[3, 1, 2]$. Then we can swap the$2$-nd and the$3$-rd elements to get$[3, 2, 1]$; - if we shift
$[1, 2, 3]$by$2$positions, we get$[2, 3, 1]$. Then we can swap the$1$-st and the$2$-nd elements to get$[3, 2, 1]$;
- if we shift
- in the fourth test case, we stated that we didn't do any swaps after the cyclic shift, but no value of cyclic shift could produce the array
$[1, 2, 3, 4, 6, 5]$.
样例
4
4 1
2 3 1 4
3 1
1 2 3
3 1
3 2 1
6 0
1 2 3 4 6 5
1 3
1 0
3 0 1 2
0
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