For an array A of length N, let F(A) denote the sum of the product of all the subarrays of A. Formally,

$F(A) = \sum_{L=1}^N \sum_{R=L}^N (\prod_{i=L}^R A_{i}\right )$

For example, let A = [1, 0, 1], then there are 6 possible subarrays:

Subarray [1, 1] has product = 1
Subarray [1, 2] has product = 0
Subarray [1, 3] has product = 0
Subarray [2, 2] has product = 0
Subarray [2, 3] has product = 0
Subarray [3, 3] has product = 1

So F(A) = 1+1 = 2.

Given a binary array A, determine the sum of F(A) over all the N! orderings of A modulo 998244353.

Note that orderings here are defined in terms of indices, not elements; which is why every array of length N has N! orderings. For example, the 3! = 6 orderings of A = [1, 0, 1] are:
[1, 0, 1] corresponding to indices [1, 2, 3]
[1, 1, 0] corresponding to indices [1, 3, 2]
[0, 1, 1] corresponding to indices [2, 1, 3]
[0, 1, 1] corresponding to indices [2, 3, 1]
[1, 1, 0] corresponding to indices [3, 1, 2]
[1, 0, 1] corresponding to indices [3, 2, 1]

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

• The first line of input will contain a single integer T, denoting the number of test cases.
• Each test case consists of multiple lines of input.
• The first line of each test case contains a single integer N denoting the le
• The second line contains N space-separated integers denoting the array A.

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

For each test case, output the sum of F(A) over all the N! orderings of A, modulo 998244353.

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

$1 ≤ T ≤ 1000$
$1 ≤ N ≤ 10^{5}$
$0 ≤ A_{i} ≤ 1$
- The sum of $N$ over all test cases won't exceed $2 \cdot 10^{5}$.

----- Sample Input 1 ------
4
3
1 0 1
1
0
2
1 1
4
1 1 0 1

----- Sample Output 1 ------
16
0
6
120

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