#include <bits/stdc++.h>
using namespace std;
template <typename T>
istream& operator>>(istream& is, vector<T>& v) {
  for (auto& i : v) is >> i;
  return is;
}
template <typename T>
ostream& operator<<(ostream& os, vector<T> v) {
  for (auto& i : v) os << i << ' ';
  return os;
}
template <typename T, typename U>
istream& operator>>(istream& is, pair<T, U>& p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T, typename U>
ostream& operator<<(ostream& os, pair<T, U> p) {
  os << p.first << ' ' << p.second;
  return os;
}
template <typename T, typename U>
void cmin(T& a, U b) {
  if (a > b) a = b;
}
template <typename T, typename U>
void cmax(T& a, U b) {
  if (a < b) a = b;
}
const int N = 2e5 + 2, M = 1e9 + 7;
int tt = 1, n, k;
void solve() {
  cin >> n;
  map<int, int> m;
  for (auto i = 0; i < n; i++) {
    int x;
    cin >> x;
    m[x]++;
  }
  long long ans = m[1];
  for (auto i = 0; i < m[0]; i++) ans *= 2;
  cout << ans << '\n';
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> tt;
  while (tt--) solve();
  return 0;
}

### Prompt

Generate 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;
template <typename T>
istream& operator>>(istream& is, vector<T>& v) {
  for (auto& i : v) is >> i;
  return is;
}
template <typename T>
ostream& operator<<(ostream& os, vector<T> v) {
  for (auto& i : v) os << i << ' ';
  return os;
}
template <typename T, typename U>
istream& operator>>(istream& is, pair<T, U>& p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T, typename U>
ostream& operator<<(ostream& os, pair<T, U> p) {
  os << p.first << ' ' << p.second;
  return os;
}
template <typename T, typename U>
void cmin(T& a, U b) {
  if (a > b) a = b;
}
template <typename T, typename U>
void cmax(T& a, U b) {
  if (a < b) a = b;
}
const int N = 2e5 + 2, M = 1e9 + 7;
int tt = 1, n, k;
void solve() {
  cin >> n;
  map<int, int> m;
  for (auto i = 0; i < n; i++) {
    int x;
    cin >> x;
    m[x]++;
  }
  long long ans = m[1];
  for (auto i = 0; i < m[0]; i++) ans *= 2;
  cout << ans << '\n';
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> tt;
  while (tt--) solve();
  return 0;
}

```