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#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int MAX = 3e5 + 213;

ll MOD = 1e9 + 7;

ll tab[MAX];
ll dp[MAX];
int N;

void solve_kwadrat()
{
    dp[0] = 1;

    for (int i = 1; i <= N; ++i)
    {
        ll suma = 0;

        for (int j = i; j > 0; --j)
        {
            ll suma_na_przedziale = (tab[i] - tab[j - 1] + MOD) % MOD;

            if (suma_na_przedziale % 2 == 0)
            {
                (suma += dp[j - 1]) %= MOD;
            }
        }

        dp[i] = suma % MOD;
    }

    cout << dp[N] % MOD << "\n";
}

void solve_male()
{
    ll mod0 = 1;
    ll mod1 = 0;

    dp[0] = 0;

    for (int i = 1; i <= N; ++i)
    {
        tab[i] %= 2;

        ll suma = 0;

        if (tab[i] == 1)
            suma = mod1;
        else
            suma = mod0;

        if (tab[i] == 1)
            (mod1 += suma) %= MOD;
        else
            (mod0 += suma) %= MOD;

        dp[i] = suma % MOD;
    }

    cout << dp[N] % MOD << "\n";
}

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

    cin >> N;

    bool suma_wieksza_niz_mod = false;

    for (int i = 1; i <= N; ++i)
    {
        cin >> tab[i];
        tab[i] += tab[i - 1];

        if (tab[i] >= MOD)
        {
            suma_wieksza_niz_mod = true;
        }
        tab[i] %= MOD;
    }

    if (N <= 3000 || suma_wieksza_niz_mod)
    {
        cerr << "Kwadrat\n";
        solve_kwadrat();
    }
    else
    {
        cerr << "Male\n";
        solve_male();
    }

    return 0;
}