#include <iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<map>
#include<set>
#include<stack>
#include<queue>
#include<math.h>
using namespace std;
typedef long long ll;
#define int long long
#define double long double
typedef vector<int> VI;
typedef pair<int, int> pii;
typedef vector<pii> VP;
typedef vector<string> VS;
typedef priority_queue<int> PQ;
template<class T>bool chmax(T &a, const T &b) { if (a < b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b < a) { a = b; return 1; } return 0; }
#define fore(i,a) for(auto &i:a)
#define REP(i,n) for(int i=0;i<n;i++)
#define eREP(i,n) for(int i=0;i<=n;i++)
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define eFOR(i,a,b) for(int i=(a);i<=(b);++i)
#define SORT(c) sort((c).begin(),(c).end())
#define rSORT(c) sort((c).rbegin(),(c).rend())
#define LB(x,a) lower_bound((x).begin(),(x).end(),(a))
#define UB(x,a) upper_bound((x).begin(),(x).end(),(a))
#define INF 1000000000
#define LLINF 9223372036854775807
#define mod 1000000007
#define mo 1000000007
#define eps 1e-12 
//priority_queue<int,vector<int>, greater<int> > q2;

long long modpow(long long a, long long n) {
	long long res = 1;
	while (n > 0) {
		if (n & 1) res = res * a % mo;
		a = a * a % mo;
		n >>= 1;
	}
	return res;
}

long long modinv(long long a) {
	return modpow(a, mod - 2);
}


signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	int N; cin >> N;
	VP A;
	int co = 0;
	bool op = 0;
	REP(i, N) {
		int a; cin >> a;
		if (a == 0) {
			op = 1;
		}
		else if (a != 1) {
			if (A.size())A.back().second += co;
			if (co)A.push_back(pii(1, co));
			A.push_back(pii(a, co));
			co = 0;
		}
		else co++;
	}
	if (A.size())A.back().second += co;
	//if (co)A.push_back(pii(1, co));
	if (op) {
		cout << 0 << endl;
		return 0;
	}
	int ans = 1;
	REP(i, A.size()) {
		int j = i;
		int cnt = A[j].first;
		
		int p = A[j].second;
		//cout << cnt << " " << p << endl;
		if (cnt == 1)continue;
		while (j < A.size() && INF > cnt) {
			//cout << j << endl;
			ans *= cnt;
			ans %= mod;
			ans *= modpow(cnt, p);
			ans %= mod;
			//cout << cnt << " " << p << endl;
			j++;
			if (j < A.size()) {
				cnt *= A[j].first;
			}
			if (cnt >= INF)break;
		}
	
	}


	cout << ans << endl;

	return 0;
}