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#include <bits/stdc++.h>
using namespace std;

int P = 1000000007;

void solve1(int n, const vector<int> &a, int sa) {
	if (sa%2 != 0) {
		cout << 0 << endl;
		return;
	}
	int dp=0,dps=0;
	int s = 0;
	for (int i=1;i<n+1;i++) {
		s += a[i];
		if (s%2==0) {
			dp = (dps + 1)%P;
			dps = (dps + dp)%P;
			//cout << dp << " " << dps << endl;
		}
	}
	cout << dp << endl;
}

void solve2(int n, const vector<int> &a) {
	vector<int> dp(n+1); dp[0]=1;
	for (int i=1;i<n+1;i++) {
		int s=0,s2=0;
		//cout << "i="<<i<<endl;
		for (int j=i;j>0;j--) {
			s = (s+a[j])%P;
			//cout << "  s="<< s << endl;
			if (s%2==0)
				s2 = (s2+dp[j-1])%P;
		}
		dp[i] = s2;
	}
	//for (int i=1;i<n+1;i++)
	//	cout << dp[i] << " ";
	cout << dp[n] << endl;
}

int main() {
	ios_base::sync_with_stdio(0);
	int n;
	cin >> n;
	vector<int> a(n+1);
	long long sa = 0;
	for (int i=1;i<n+1;i++) {
		cin >> a[i];
		sa += a[i];
	}
	if (sa<P)
		solve1(n,a,sa);
	else
		solve2(n,a);
	return 0;
}