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CF1582B.Luntik and Subsequences
Luntik and Subsequences
Luntik came out for a morning stroll and found an array of length . He calculated the sum of the elements of the array (). Luntik calls a subsequence of the array nearly full if the sum of the numbers in that subsequence is equal to .
Luntik really wants to know the number of nearly full subsequences of the array . But he needs to come home so he asks you to solve that problem!
A sequence is a subsequence of a sequence if can be obtained from by deletion of several (possibly, zero or all) elements.
Input
The first line contains a single integer () — the number of test cases. The next lines contain descriptions of test cases. The description of each test case consists of two lines.
The first line of each test case contains a single integer () — the length of the array.
The second line contains integers () — the elements of the array .
Output
For each test case print the number of nearly full subsequences of the array.
Note
In the first test case, , only is a nearly full subsequence among all subsequences, the sum in it is equal to .
In the second test case, there are no nearly full subsequences.
In the third test case, , the nearly full subsequences are and (the sum of an empty subsequence is ).
Samples
5
5
1 2 3 4 5
2
1000 1000
2
1 0
5
3 0 2 1 1
5
2 1 0 3 0
1
0
2
4
4
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