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#include <bits/stdc++.h>

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define debug std::cout << "hmm" << std::endl;
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll, ll> pll;
typedef std::vector<int> vi;
typedef std::vector<ll> vl;

template <typename T>
void print(const T &t)
{
    std::cout << t << ' ';
}
template <typename T1, typename T2>
void print(const std::pair<T1, T2> &t)
{
    std::cout << '{' << t.first << ' ' << t.second << '}';
}
template <typename T>
void print(const std::vector<T> &t)
{
    for (auto a : t)
        print(a);
    std::cout << std::endl;
}

const ll MOD = 1000000007;

main()
{
    std::cin.tie(0)->sync_with_stdio(0);
    std::cin.exceptions(std::cin.failbit);

    int Z = 1;
    //std::cin >> Z;
    while (Z--)
    {
        int n;
        std::cin >> n;
        vl V(n);
        ll W = 0;
        for (auto &a : V)
        {
            std::cin >> a;
            W += a;
        }
        if (W < MOD)
        {
            std::vector<pll> DP(n);
            if (V[0] & 1)
                DP[0] = {0, 1};
            else
                DP[0] = {1, 0};
            for (int i = 1; i < n; i++)
                if (V[i] % 2)
                    DP[i] = {DP[i - 1].second, DP[i - 1].first};
                else
                    DP[i] = {(2 * DP[i - 1].first) % MOD, DP[i - 1].second};
            std::cout << DP.back().first << std::endl;
        }
        else
        {
            vl DP(n + 1, 0);
            DP[0] = 1;
            for (int i = 1; i <= n; i++)
            {
                ll S = V[i - 1];
                for (int j = 1; j <= i; j++)
                {
                    if (!(S & 1))
                        DP[i] = (DP[i] + DP[i - j]) % MOD;
                    if (i - j - 1 >= 0)
                        S = (S + V[i - j - 1]) % MOD;
                }
            }
            std::cout << DP.back() << std::endl;
        }
    }
}