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).
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

public class _1582_B {

    private static final FastScanner in = new FastScanner();
    private static final PrintWriter out = new PrintWriter(System.out);
    private static final PrintWriter err = new PrintWriter(System.err);

    public static void solve() {
        int n = in.nextInt();
        int[] arr = in.nextIntArray(n);

        int count1 = 0;
        int count0 = 0;

        for (int i = 0; i < n; i++) {
            int a = arr[i];
            if (a == 0) count0++;
            if (a == 1) {
                if (i == 0 || arr[i-1] != 1)
                    count1++;
            }
        }

        out.println(count1 * (1 << count0));
    }

    // Boilerplate
    public static void main(String[] args) {
        int t = in.nextInt();
        while (t-- > 0) {
            solve();
        }

        err.close();
        out.close();
    }

    @SuppressWarnings("unused")
    static class FastScanner {

        StringTokenizer tok = new StringTokenizer("");
        BufferedReader in;

        FastScanner() {
            in = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (!tok.hasMoreElements()) {
                try {
                    tok = new StringTokenizer(in.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }

            return tok.nextToken();
        }

        String nextLine() {
            String line;
            try {
                line = in.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            return line;
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        int[] nextIntArray(int n) {
            int[] arr = new int[n];
            for (int i = 0; i < n; i++) {
                arr[i] = nextInt();
            }
            return arr;
        }

        List<Integer> nextIntegerList(int n) {
            ArrayList<Integer> list = new ArrayList<>(n);
            for (int i = 0; i < n; i++) {
                list.add(nextInt());
            }
            return list;
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        long[] nextLongArray(int n) {
            long[] arr = new long[n];
            for (int i = 0; i < n; i++) {
                arr[i] = nextLong();
            }
            return arr;
        }

        List<Long> nextLongList(int n) {
            ArrayList<Long> list = new ArrayList<>(n);
            for (int i = 0; i < n; i++) {
                list.add(nextLong());
            }
            return list;
        }

        ArrayList<Integer>[] nextGraph(int n, int m) {
            @SuppressWarnings("unchecked")
            ArrayList<Integer>[] adj = (ArrayList<Integer>[]) new ArrayList[n];

            for (int i = 0; i < n; i++) {
                adj[i] = new ArrayList<>();
            }

            for (int i = 0; i < m; i++) {
                int v = nextInt();
                int t = nextInt();
                adj[v - 1].add(t - 1);
                adj[t - 1].add(v - 1);
            }

            return adj;
        }
    }
}