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

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

    const int MOD = 1e9 + 7;

    int n;
    cin >> n;
    vector<int> nums(n);
    for(int& i : nums) {
        cin >> i;
    }

    ll ans = 0;
    auto mod = [&](ll& a) {
        if(a >= MOD)
            a -= MOD;
    };

    function<void(int)> f = [&](int beg) {
        ll s = 0;
        for(int i = beg; i < n; i++) {
            s += nums[i];
            mod(s);

            if(!(s & 1)) {
                if(i == n - 1) {
                    ans++;
                    mod(ans);
                }
                else
                    f(i + 1);
            }
        }
    };

    f(0);

    cout << ans << "\n";

    return 0;
}