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

using ull = unsigned long long;
int n;
constexpr ull mod = 1e9 + 7;
ull a;
vector<ull> dp;
vector<ull> sp;

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

    cin >> n;
    dp.resize(n + 1);
    sp.resize(n + 1);
    dp[0] = 1;
    sp[0] = 0;
    for (int i = 1; i <= n; ++i)
    {
        cin >> a;
        sp[i] = sp[i - 1] + a;
    }
    for (int i = 0; i < n; ++i)
    {
        for (int j = i; j >= 0; --j)
        {
            if (!(((sp[i + 1] - sp[j]) % mod) & 1))
            {
                dp[i + 1] += dp[j];
                dp[i + 1] %= mod;
            }
        }
    }
    if (n == 1 && sp[1] & 1)
        cout << "0\n";
    else
        cout << dp[n] % mod << '\n';
}