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.BufferedOutputStream;
  import java.io.BufferedReader;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintStream;
  import java.io.PrintWriter;
  import java.util.*;
  
  public class Mainnn {
  
      // static final File ip = new File("input.txt");
      // static final File op = new File("output.txt");
      // static {
      //     try {
      //         System.setOut(new PrintStream(op));
      //         System.setIn(new FileInputStream(ip));
      //     } catch (Exception e) {
      //     }
  
      //     // in = new InputReader(System.in);
      // }
      private static final PrintWriter out = new PrintWriter(System.out);
  
  
      public static void main(String[] args) {
          MyScanner sc = new MyScanner();
          // out = new PrintWriter(new BufferedOutputStream(System.out));
  
          // out.println(result); // print via PrintWriter
          /////////////////////////////////////////////
  
          int test = sc.nextInt();
          while (test-- != 0) {
              int n = sc.nextInt();
              long[] a = new long[n];
              long one=0,zero=0;
              int f = 0;
              for(int i=0;i<n;i++)
              {
                  a[i] = sc.nextLong();
                  if(a[i] == 1) one++;
                  else if(a[i] == 0) zero++;
                  else f=1;
              }
              if(one==0) System.out.println(0);
              else if(zero == 0) System.out.println(one);
              else
              {
                  // if(one==1 && zero==1) System.out.println(2);
                  // else if(one == 1) System.out.println(one+((long) Math.pow(2, zero)-1)*one+1);
                  // else System.out.println(one+((long) Math.pow(2, zero)-1)*one);
                  System.out.println(one+((long) Math.pow(2, zero)-1)*one);
              }
          }
      }
  
      static long power(long x, long y, long p) {
          long res = 1;
          x = x % p;
          if (x == 0)
              return 0;
          while (y > 0) {
              if ((y & 1) != 0)
                  res = (res * x) % p;
              y = y >> 1;
              x = (x * x) % p;
          }
          return res;
      }
  
      static void sortI(int[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              int tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      static void sortL(long[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              long tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      private static long gcd(long a, long b) {
          return (a == 0 ? b : gcd(b % a, a));
      }
  
      static class pair implements Comparator<pair> {
          long a;
          int b;
  
          pair(long x, int y) {
              this.a = x;
              this.b = y;
          }
  
          public int compare(pair p1, pair p2) {
              if (p1.a > p2.a)
                  return 1;
              else if (p1.a < p2.a)
                  return -1;
              return 0;
          }
      }
  
      static class first implements Comparator<pair> {
  
          public int compare(pair p1, pair p2) {
              if (p1.a > p2.a)
                  return 1;
              else if (p1.a < p2.a)
                  return -1;
              return 0;
          }
      }
  
      static class second implements Comparator<pair> {
  
          public int compare(pair p1, pair p2) {
              if (p1.b > p2.b)
                  return 1;
              else if (p1.b < p2.b)
                  return -1;
              return 0;
          }
      }
  
      // -----------PrintWriter for faster output---------------------------------
  
      // -----------MyScanner class for faster input----------
      public static class MyScanner {
          BufferedReader br;
          StringTokenizer st;
  
          public MyScanner() {
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          String next() {
              while (st == null || !st.hasMoreElements()) {
                  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());
          }
  
          double nextDouble() {
              return Double.parseDouble(next());
          }
  
          String nextLine() {
              String str = "";
              try {
                  str = br.readLine();
              } catch (IOException e) {
                  e.printStackTrace();
              }
              return str;
          }
  
      }
      // --------------------------------------------------------
  }