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#include <bits/stdc++.h>

using namespace std;
const int MAX = 3e5 + 7;
const int MOD = 1e9 + 7;
typedef long long ll;
ll dp[MAX], pref[MAX];

int solve_1(int n){
	ll sum = 1;
	for(int i = 1; i <= n; i++){
		if(!(pref[i]&1)){
			dp[i] = sum;
			sum <<= 1;
			sum %= MOD;
		}
	}
	
	return dp[n];
}

int solve_2(int n){
	dp[0] = 1;
	for(int i = 1; i <= n; i++){
		for(int j = 1; j <= i; j++){
			if(((pref[i] - pref[j-1]+MOD)%MOD)%2 == 0) {
				dp[i] += dp[j-1];
				dp[i] %= MOD;
			}
		}
	}
	
	return dp[n];
}

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	for(int i = 1, a; i <= n; i++){
		cin >> a;
		pref[i] = (pref[i-1] + a)%MOD;
	}
	if(n <= 3e4) cout << solve_2(n);
	else cout << solve_1(n);
	
	return 0;
}