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

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

    int a;
    cin >> a;

    int tab[a];
    bool flaga = 1;

    for(int i = 0; i < a; i++)
    {
        cin >> tab[i];

        if(tab[i] > 100)
        {
            flaga = 0;
        }
    }

    if(a <= 3000)
    {
        long long suma;
        long long dp[a + 1];

        dp[0] = 1;

        for(int i = 1; i <= a; i++)
        {
            suma = 0;
            dp[i] = 0;

            for(int x = i - 1; x >= 0; x--)
            {
                suma += tab[x];
                suma %= 1000000007;

                if(suma % 2 == 0)
                {
                    dp[i] += dp[x];
                    dp[i] %= 1000000007;
                }
            }
        }

        cout << dp[a] << endl;

        return 0;
    }

    if(flaga == 1)
    {
        long long dp[a][3];

        if(tab[0] % 2 == 0)
        {
            dp[0][0] = 1;
            dp[0][1] = 0;
            dp[0][2] = 0;
        }
        else
        {
            dp[0][0] = 0;
            dp[0][1] = 1;
            dp[0][2] = 0;
        }

        for(int i = 1; i < a; i++)
        {
            if(tab[i] % 2 == 1)
            {
                dp[i][0] = dp[i - 1][1] + dp[i - 1][2];
                dp[i][1] = dp[i - 1][0];
                dp[i][2] = dp[i - 1][0];
            }
            else
            {
                dp[i][0] = 2 * dp[i - 1][0];
                dp[i][1] = dp[i - 1][1];
                dp[i][2] = dp[i - 1][2];
            }
        }

        cout << dp[a - 1][0] << endl;

        return 0;
    }

    cout << "I REALLY DON'T KNOW AND DON'T CARE" << endl;

    return 0;
}