human
Give me a Python code to print the number of nearly full subsequences of the array given the following:
Luntik came out for a morning stroll and found an array a of length n. He calculated the sum s of the elements of the array (s= ∑_{i=1}^{n} a_i). Luntik calls a subsequence of the array a nearly full if the sum of the numbers in that subsequence is equal to s-1.

Luntik really wants to know the number of nearly full subsequences of the array a. But he needs to come home so he asks you to solve that problem!

A sequence x is a subsequence of a sequence y if x can be obtained from y by deletion of several (possibly, zero or all) elements.

Input

The first line contains a single integer t (1 ≤ t ≤ 1000) — the number of test cases. The next 2 ⋅ t 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 n (1 ≤ n ≤ 60) — the length of the array.

The second line contains n integers a_1, a_2, …, a_n (0 ≤ a_i ≤ 10^9) — the elements of the array a.

Output

For each test case print the number of nearly full subsequences of the array.

Example

Input

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

Output

1
0
2
4
4

Note

In the first test case, s=1+2+3+4+5=15, only (2,3,4,5) is a nearly full subsequence among all subsequences, the sum in it is equal to 2+3+4+5=14=15-1.

In the second test case, there are no nearly full subsequences.

In the third test case, s=1+0=1, the nearly full subsequences are (0) and () (the sum of an empty subsequence is 0).
assistant
#Here is Python code to print the number of nearly full subsequences of the array.

# import pytest

# @pytest.mark.parametrize(
#     'array, expected', [
#         [[1, 2, 3, 4, 5], 1],
#         [[1000, 1000], 0],
#         [[1, 0], 2],
#         [[3, 0, 2, 1, 1], 4],
#         [[2, 1, 0, 3, 0], 4],
#     ]
# )
# def test_luntik(array, expected):
#     result = luntik(array)
#     assert expected == result

def luntik(array):
    # Calculates number of nearly-full subsequences
    zeroes = array.count(0)
    ones = array.count(1)

    return ones * (2 ** zeroes)

# if __name__ == '__main__':
for i in range(int(input())):
    input()
    array = list(map(int, input().split()))
    print(luntik(array))