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Ridbit is given an array $a_{1}, a_{2}, \ldots, a_{N}$. He needs to find the number of ways to divide the array into contiguous subarrays such that:
Each element of the sequence $a$ belongs to exactly one of the subarrays.
There is an integer $m$ such that the MEX of every subarray is equal to $m$. The MEX of a sequence is the smallest non-negative integer which does not occur in this sequence.

Help Ridbit with this task.

------ Input ------
The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
The first line of each test case contains a single integer $N$.
The second line contains $N$ space-separated integers $a_{1}, a_{2}, \ldots, a_{N}$.

------ Output ------
For each test case, print a single line containing one integer ― the number of ways to divide the sequence, modulo $10^{9} + 7$.

------ Constraints ------
$1 ≤ T ≤ 10$
$1 ≤ N ≤ 100,000$
$0 ≤ a_{i} ≤ N$ for each valid $i$

----- Sample Input 1 ------
2

6

1 0 0 1 0 1

3

1 2 3
----- Sample Output 1 ------
5

4
----- explanation 1 ------
Example case 1: The five valid ways to divide the sequence are:
- $[1, 0, 0, 1, 0, 1]$
- $[1, 0], [0, 1, 0, 1]$
- $[1, 0, 0], [1, 0, 1]$
- $[1, 0, 0, 1], [0, 1]$
- $[1, 0], [0, 1], [0, 1]$

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