You are given a sequence $a$ of length $n$ consisting of $0$s and $1$s.
You can perform the following operation on this sequence:
- Pick an index
$i$from$1$to$n-2$(inclusive). - Change all of
$a_{i}$,$a_{i+1}$,$a_{i+2}$to$a_{i} \oplus a_{i+1} \oplus a_{i+2}$simultaneously, where$\oplus$denotes the bitwise XOR operation
Find a sequence of
at most
$n$ operations that changes all elements of $a$ to $0$s or report that it's impossible.
We can prove that if there exists a sequence of operations of any length that changes all elements of $a$ to $0$s, then there is also such a sequence of length not greater than $n$.
Input
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^4$).
The first line of each test case contains a single integer $n$ ($3 \le n \le 2\cdot10^5$) — the length of $a$.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($a_i = 0$ or $a_i = 1$) — elements of $a$.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2\cdot10^5$.
Output
For each test case, do the following:
- if there is no way of making all the elements of
$a$equal to$0$after performing the above operation some number of times, print "NO". - otherwise, in the first line print "
YES", in the second line print$k$($0 \le k \le n$) — the number of operations that you want to perform on$a$, and in the third line print a sequence$b_1, b_2, \dots, b_k$($1 \le b_i \le n - 2$) — the indices on which the operation should be applied.
If there are multiple solutions, you may print any.
Note
In the first example, the sequence contains only $0$s so we don't need to change anything.
In the second example, we can transform $[1, 1, 1, 1, 0]$ to $[1, 1, 0, 0, 0]$ and then to $[0, 0, 0, 0, 0]$ by performing the operation on the third element of $a$ and then on the first element of $a$.
In the third example, no matter whether we first perform the operation on the first or on the second element of $a$ we will get $[1, 1, 1, 1]$, which cannot be transformed to $[0, 0, 0, 0]$.
样例
3
3
0 0 0
5
1 1 1 1 0
4
1 0 0 1
YES
0
YES
2
3 1
NO
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