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#include <iostream>
#include <vector>

using namespace std;

int n;
int a[300003];
int T[300003];
int mod = 1000000007;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n;

    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }
    T[0] = 1 - (a[0] % 2);
    std::vector<int> sums;
    sums.push_back(a[0]);
    for (int i = 1; i < n; ++i) {
        sums.push_back(0);
        for (int j = i; j > 0; --j) {
            if (((a[i] + sums[j]) % mod) % 2 == 0) {
                T[i] = (T[i] + T[j - 1]) % mod;
            }
            sums[j] = (sums[j] + a[i]) % mod;
        }
        if (((a[i] + sums[0]) % mod) % 2 == 0) {
            T[i] = (T[i] + 1) % mod;
        }
        sums[0] = (sums[0] + a[i]) % mod;
    }
    cout << T[n - 1];
    return 0;
}