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CF1760D.Challenging Valleys
Challenging Valleys
You are given an array of integers. This array is called a "valley" if there exists exactly one subarray such that:
- ,
- ,
- or ,
- or .
Here are three examples:

The first image shows the array [], it is a valley because only subarray with indices satisfies the condition.
The second image shows the array [], it is a valley because only subarray with indices satisfies the codition.
The third image shows the array [], it is not a valley because two subarrays and that satisfy the condition.
You are asked whether the given array is a valley or not.
Note that we consider the array to be indexed from .
Input
The first line contains a single integer () — the number of test cases.
The first line of each test case contains a single integer () — the length of the array.
The second line of each test case contains integers () — the elements of the array.
It is guaranteed that the sum of over all test cases is smaller than .
Output
For each test case, output "YES" (without quotes) if the array is a valley, and "NO" (without quotes) otherwise.
You can output the answer in any case (for example, the strings "yEs", "yes", "Yes" and "YES" will be recognized as a positive answer).
Note
The first three test cases are explained in the statement.
Samples
6
7
3 2 2 1 2 2 3
11
1 1 1 2 3 3 4 5 6 6 6
7
1 2 3 4 3 2 1
7
9 7 4 6 9 9 10
1
1000000000
8
9 4 4 5 9 4 9 10
YES
YES
NO
YES
YES
NO
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