Suppose you have a binary array B of length N.
$A sequence x_{1}, x_{2}, \ldots, x_{k}$ is called good with respect to B if it satisfies the following conditions:
1 ≤ $x_{1} < x_{2} < \ldots < x_{k}$ ≤ N+1
For every pair (i, j) such that 1 ≤ i < j ≤ k, the subarray B[x_{i}: x_{j}-1] contains (j-i) more ones than zeros.
- That is, if B[x_{i} : x_{j}-1] contains c_{1} ones and c_{0} zeros, then c_{1} - c_{0} = j-i must hold.

Here, B[L: R] denotes the subarray consisting of elements $[B_{L}, B_{L+1}, B_{L+2}, \ldots, B_{R}]$.
Note that in particular, a sequence of size 1 is always good.

For example, suppose B = [0,1,1,0,1,1]. Then,
The sequence [1,4,7] is a good sequence. The subarrays that need to be checked are B[1:3], B[1:6] and B[4:6], which all satisfy the condition.
The sequence [1, 5] is not good, because B[1:4] = [0, 1, 1, 0] contains an equal number of zeros and ones (when it should contain one extra 1).

Alice gave Bob a binary array A of size N and asked him to find the longest sequence that is good with respect to A. Help Bob find one such sequence.
If multiple possible longest sequences exist, you may print any of them.

------ Input Format ------

• The first line of input will contain a single integer T, denoting the number of test cases.
• Each test case consists of two lines of input.
• The first line of each test case contains a single integer N — the size of the binary array.
• The second line contains N space-separated numbers — $A_{1} , A_{2} , \ldots , A_{N}$.

------ Output Format ------

Each test case requires two lines of output:
- First, print on a new line a single integer K — the maximum length of a sequence that is good with respect to A
- On the next line, print K space-separated integers in increasing order, denoting the indices of one such sequence.

If there are multiple possible good sequences with maximum size, output any of them.

------ Constraints ------

$1 ≤ T ≤ 10^{5}$
$1 ≤ N ≤ 10^{5}$
$0 ≤ A_{i} ≤ 1$
- The sum of $N$ over all test cases won't exceed $10^{6}$.

----- Sample Input 1 ------
4
6
0 1 1 0 1 1
5
0 1 0 1 0
4
1 1 1 1
3
1 0 0
----- Sample Output 1 ------
4
2 5 6 7
2
4 5
5
1 2 3 4 5
2
1 2
----- explanation 1 ------
Test case $1$: We have $A = [0, 1, 1, 0, 1, 1]$. The sequence $[2, 5, 6, 7]$ requires us to check $6$ subarrays:
- $A[2:4] = [1, 1, 0]$ which has $c_{1} - c_{0} = 1$ and corresponds to $i = 1, j = 2$
- $A[2:5] = [1, 1, 0, 1]$ which has $c_{1} - c_{0} = 2$ and corresponds to $i = 1, j = 3$
- $A[2:6] = [1, 1, 0, 1, 1]$ which has $c_{1} - c_{0} = 3$ and corresponds to $i = 1, j = 4$
- $A[5:5] = [1]$, which has $c_{1} - c_{0} = 1$ and corresponds to $i = 2, j = 3$
- $A[5:6] = [1, 1]$, which has $c_{1} - c_{0} = 2$ and corresponds to $i = 2, j = 4$
- $A[6:6] = [1]$, which has $c_{1} - c_{0} = 1$ and corresponds to $i = 3, j = 4$

As you can see, all $6$ pairs satisfy the condition.

Test case $2$: The only subarray that needs to be checked is $A[4:4] = [1]$, which has $c_{1} - c_{0} = 1$ as needed. It can be verified that no good sequence of length greater than $2$ exists.

见题面

见题面