description: 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).
solution: import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.StringTokenizer;
  
  public class Solution{
  	
  	static int max(int[] arr,int n){
  		int mx = Integer.MIN_VALUE;
  		for(int i = 0;i < n;i++){
  			if(arr[i] > mx){
  				mx = arr[i];
  			}
  		}
  		return mx;
  	}
  
  	static int min(int[] arr,int n){
  		int mn = Integer.MAX_VALUE;
  		for(int i = 0;i < n;i++){
  			if(arr[i] < mn){
  				mn = arr[i];
  			}
  		}
  		return mn;
  	}
  
  	static void sort(int[] arr) {
  		ArrayList<Integer> l = new ArrayList<>();
  		for (int i:arr) l.add(i);
  		Collections.sort(l);
  		for (int i = 0; i < arr.length; i++) arr[i] = l.get(i);
  	}
  
  	static class FastScanner {
  		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer st=new StringTokenizer("");
  		String next() {
  			while (!st.hasMoreTokens())
  				try {
  					st=new StringTokenizer(br.readLine());
  				} catch (IOException e) {
  					e.printStackTrace();
  				}
  			return st.nextToken();
  		}
  		int nextInt(){
  			return Integer.parseInt(next());
  		}
  		long nextLong(){
  			return Long.parseLong(next());
  		}
  		float nextFloat(){
  			return Float.parseFloat(next());
  		}
  		double nextDouble(){
  			return Double.parseDouble(next());
  		}
  		int[] int_arr(int n){
  			int arr[] = new int[n];
  			for(int i = 0;i < n;i++) arr[i] = nextInt();
  			return arr;
  		}
  		long[] l_arr(int n){
  			long arr[] = new long[n];
  			for(int i = 0;i < n;i++) arr[i] = nextLong();
  			return arr;
  		}
  	}
  
  	static int bound(int[] arr,int start,int end,int x,boolean lower){
  		int ans = -1;
  		while(start <= end){
  			int mid = start + (end - start) / 2;
  			if(arr[mid] > x) end = mid - 1;
  			else if(arr[mid] < x) start = mid + 1;
  			else{
  				ans = mid;
  				if(lower) end = mid - 1;
  				else start = mid + 1;
  			}
  		}
  		return ans;
  	}
  
  	static boolean isPrime(int n){
          if(n == 1){
              return false;
          }
          if(n == 2 || n == 3){
              return true;
          }
          if(n % 2 == 0 || n % 3 == 0){
              return false;
          }
          for(long i = 5; i*i <= n; i += 6){
              if(n % i == 0 || n % (i + 2) == 0)
                  return false;
          }
          return true;
      }
  
  	static int l = 10000000;
  	static boolean[] sieve = new boolean[l+1];
  	static void primes(){
  		Arrays.fill(sieve,true);
  		for(int i = 2;i * i <= l;i++){
  			if(sieve[i]){
  				for(int j = i * i;j <= l;j += i){
  					sieve[j] = false;
  				}
  			}
  		}
  	}
  
  	public int bs(int[] arr,int start,int end,int target){
  		while(start <= end){
  			int mid = start + (end - start) / 2;
  			if(arr[mid] == target){
  				return mid;
  			}
  			else if(arr[mid] > target){
  				end = mid - 1;
  			}
  			else{
  				start = mid + 1;
  			}
  		}
  		return -1;
  	}
  
  	public static void main(String[] args){
  		FastScanner in = new FastScanner();
  		PrintWriter out = new PrintWriter(System.out);
  
  		int t = in.nextInt();
  		while(t --> 0){
  			int n = in.nextInt();
  			long one = 0,zero = 0,ele;
  			for(int i = 0;i < n;i++){
  				ele = in.nextInt();
  				if(ele == 1){
  					one += 1l;
  				}
  				else if(ele == 0){
  					zero += 1l;
  				}
  			}
  			System.out.println((1l << zero) * one);
  		}
  		out.close();
  		
      }
  }
  