#include <cstdio>
#include <iostream>

using namespace std;

const int N = 1145;
const long long MOD = 1e9 + 7;

int n;
long long a;
long long b;
long long ans;

long long pow (long long a, long long n) {
	long long res = 1;
	while (n) {
		if (n & 1) {
			res = res * a % MOD;
		}
		a = a * a % MOD;
		n >>= 1;
	}
	return res;
}

int main () {
	
	freopen ("01.in", "r", stdin);
	freopen ("01.out", "w", stdout);

	cin >> n;
	int num;
	for (int i = 1; i <= n; i++) {
		cin >> num;
		a += num;
	}
	b = n - a;

	a = pow (2, a);
	b = pow (2, b);
	ans = pow ((a + b) % MOD, n);
	cout << ans << endl;
	
	return 0;
}