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#include <iostream>
#include <algorithm>

using namespace std;

int main() {
    ios::sync_with_stdio(false);

    int n, a_limit = 1000, even_prefixes = 0;
    bool limit_exceeded = false;
    long long mod = 1e9 + 7, res = 0;

    cin >> n;

    long long tab[n];
    long long prefix_sum[n];

    cin >> tab[0];
    prefix_sum[0] = tab[0];

    for (auto i = 1; i < n; i++) {
        cin >> tab[i];

        if (tab[i] > a_limit) {
            limit_exceeded = true;
        }

        prefix_sum[i] = prefix_sum[i - 1] + tab[i];
        prefix_sum[i] %= mod;
    }

    if (!limit_exceeded) {
        if (prefix_sum[n - 1] % 2 != 0) {
            cout << 0;
        } else {
            for(auto i = 0; i < n - 1; i++) {
                if (prefix_sum[i] % 2 == 0) even_prefixes++;
            }

            res = 1;
            while(even_prefixes > 0) {
                res *= 2;
                res %= mod;
                even_prefixes--;
            }

            cout << res;
        }

    } else {
        long long num_of_possibilities_prefix[n];
        long long prefix_diff;

        for (auto i = 0; i < n; i++) {
            num_of_possibilities_prefix[i] = (prefix_sum[i] % 2 == 0) ? 1 : 0;

            for (auto j = 1; j <= i; j++) {
                prefix_diff = prefix_sum[i] - prefix_sum[j - 1];
                if (prefix_diff < 0) prefix_diff += mod;

                if (prefix_diff % 2 == 0) {
                    num_of_possibilities_prefix[i] += num_of_possibilities_prefix[j - 1];
                    num_of_possibilities_prefix[i] %= mod;
                }
            }
        }

        cout << num_of_possibilities_prefix[n - 1];
    }




    return 0;
}