#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e8;
const int maxn = 1e5 + 2;
void init() {
  cin.tie(NULL);
  ios_base::sync_with_stdio(false);
}
void solve() {
  long long n;
  cin >> n;
  vector<long long> arr(n, 0);
  long long a = 0, b = 0;
  for (auto &x : arr) {
    cin >> x;
    if (x == 0) a++;
    if (x == 1) b++;
  }
  long long ans = 1LL << a;
  ans *= (long long)b;
  cout << ans << '\n';
}
int main() {
  init();
  int tc = 1;
  cin >> tc;
  while (tc) {
    solve();
    tc--;
  }
}

### Prompt

Develop a solution in CPP to the problem described below:

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;
const int MOD = 1e8;
const int maxn = 1e5 + 2;
void init() {
  cin.tie(NULL);
  ios_base::sync_with_stdio(false);
}
void solve() {
  long long n;
  cin >> n;
  vector<long long> arr(n, 0);
  long long a = 0, b = 0;
  for (auto &x : arr) {
    cin >> x;
    if (x == 0) a++;
    if (x == 1) b++;
  }
  long long ans = 1LL << a;
  ans *= (long long)b;
  cout << ans << '\n';
}
int main() {
  init();
  int tc = 1;
  cin >> tc;
  while (tc) {
    solve();
    tc--;
  }
}

```