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#include <bits/stdc++.h>

#define DEBUG(x) cout << '>' << #x << ':' << x << endl;
#define fi first
#define se second
#define ll long long
#define ld long double
#define pb push_back
#define vi vector<int>
#define MAXN 100001

using namespace std;

const ll P = 1000000000 + 7;
const ll O = 1;

int parity(ll x) {
    return x & O;
}

ll last_try(int n, vector<ll> &A, vector<ll> &S) {
	vector<int> L(n, 0);
	vector<int> R(n, 0);
	L[0] = -1;
	R[0] = 0;
	R[1] = (parity(A[1]) == 0) ? 1 : 0;
	L[1] = (parity(A[1]) == 0) ? -1 : 1;


	for(int i=2; i<n; i++) {
		L[i] = L[i-1];

		if(parity(A[i]) == 0) {
			R[i] = R[i-1]*2;
		} else {
			L[i] = i;

			if(L[i-1] == -1) {
				R[i] = 0;
			} else {
				int l = L[i-1];
				if(l-1 == 0)
					R[i] = 1;
				else 
					R[i] = R[l-1]*2;
			}
		}
		R[i] %= P;
	}
	
	return R[n-1] % P;
}

ll brute_time(int n, vector<ll> &A, vector<ll> &S) {
	vector<int> R(n, 0);
	R[0] = 1;
	ll r= 0;

	for(int q = 1; q < n; q++) {
		for(int p=1; p <=q; p++) {
			ll s = S[q] - S[p-1];
			bool ok = ((s % P) % 2 == 0);

			if(ok) {
				R[q] += R[p-1];
				R[q] %= P;
			}
		}
	}

	return R[n-1];
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n;
    cin >> n;

    n++;
    vector<ll> A(n);
    vector<ll> S(n, 0);
    for (int i = 1; i < n; i++)
        cin >> A[i];

    bool over = false;

    S[0] = A[0];
    for (int i = 1; i < n; i++) {
        S[i] = A[i] + S[i - 1];
        if (S[i] >= P)
            over = true;
    }

    ll r = 0;
	// over = true;
    if (!over) {
        r = last_try(n, A, S);
    } else {
		r = brute_time(n, A, S);
    }

    cout << r << endl;

    return 0;
}