#include <bits/stdc++.h>
using namespace std;
long long a[66];
int n;
long long qmi(long long a, long long b) {
  long long res = 1;
  while (b) {
    if (b & 1) res *= a;
    a *= a;
    b >>= 1;
  }
  return res;
}
int main() {
  int t;
  scanf("%d", &t);
  while (t--) {
    scanf("%d", &n);
    long long sum = 0, x = 0, y = 0;
    for (int i = 1; i <= n; i++) {
      scanf("%lld", a + i);
      sum += a[i];
      if (!a[i]) x++;
      if (a[i] == 1) y++;
    }
    long long ans = y * qmi(2, x);
    printf("%lld\n", ans);
  }
  return 0;
}

### Prompt

Your challenge is to write a CPP solution to the following problem:

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).

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
long long a[66];
int n;
long long qmi(long long a, long long b) {
  long long res = 1;
  while (b) {
    if (b & 1) res *= a;
    a *= a;
    b >>= 1;
  }
  return res;
}
int main() {
  int t;
  scanf("%d", &t);
  while (t--) {
    scanf("%d", &n);
    long long sum = 0, x = 0, y = 0;
    for (int i = 1; i <= n; i++) {
      scanf("%lld", a + i);
      sum += a[i];
      if (!a[i]) x++;
      if (a[i] == 1) y++;
    }
    long long ans = y * qmi(2, x);
    printf("%lld\n", ans);
  }
  return 0;
}

```