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CF2164A.Sequence Game
Sequence Game
Given an integer sequence of length denoted as and an integer .
You can perform the following operation: select two adjacent numbers and and replace them with an integer , which satisfies . After the replacement, the original and are removed from the sequence, and the elements are renumbered from to .
For example, for you can select and , and replace them with . After that, becomes . However, you cannot select and and replace them with (since is bigger than , nor can you select and (the selected numbers should be adjacent).
Clearly, after performing operations, only one number will remain. The question is whether this final number can be exactly equal to .
Input
Each test contains multiple test cases. The first line contains the number of test cases (). The description of the test cases follows.
The first line of each test case contains one integer ().
The second line of each test case contains integers ().
The third line of each test case contains one integer ().
Output
For each test case, output "YES" (without quotes) if the final number can be exactly equal to , and "NO" otherwise.
You can output "YES" and "NO" in any case (for example, strings "yES", "yes" and "Yes" will be recognized as a positive response).
Note
In the first test case, you can first select and , and replace them with . After that, becomes . Now you can select and , and replace them with .
In the second test case, it can be shown that the final number can never be .
Samples
3
3
2 7 5
4
5
-1 3 7 -9 -2
8
6
1 -1 -4 5 1 -4
-2
YES
NO
YES
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