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CF1856B.Good Arrays
Good Arrays
You are given an array of positive integers of length .
Let's call an array of positive integers of length good if:
- for all from to ,
- .
Does a good array exist?
Input
Each test contains multiple test cases. The first line of input contains a single integer () — the number of test cases. The description of the test cases follows.
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 does not exceed .
Output
For each test case, output "YES" (without quotes) if there exists a good array, and "NO" (without quotes) otherwise.
You can output the answer in any case (upper or lower). For example, the strings "yEs","yes", "Yes", and "YES" will be recognized as positive responses.
Note
In the first test case, a possible good array is . Some examples of not good arrays are:
- — the array does not consist of only positive integers,
- — the array does not have the same sum as the given array,
- — the third element is equal to the third element of the given array.
In the second test case, is the only array of positive integers of length that has the sum of it's elements equal to . Since is not a good array, the answer is "NO".
Samples
6
3
6 1 2
2
1 1
4
3 1 2 4
1
17
5
1 2 1 1 1
3
618343152 819343431 1000000000
YES
NO
YES
NO
NO
YES
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