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#include <bits/stdc++.h>
#define DEBUG 0
using namespace std;

const int S = 524288, mod = 1000000007;
long long sc[S * 2][4];

long long query(int w, int p, int k, int pp, int kk, int tt)
{
    if (DEBUG)
        if (w == 1)
            cout << "Z " << pp << ' ' << kk << ' ' << tt << ' ';
    if (pp > k || kk < p)
    {
        if (DEBUG)
            if (w == 1)
                cout << " UU \n";
        return 0;
    }
    if (pp <= p && kk >= k)
    {
        // cout << "W " << w << ' ' << p << ' ' << k << ' ' << sc[w][tt] << '\n';
        return sc[w][tt];
        if (DEBUG)
            if (w == 1)
                cout << " XX \n";
    }
    long long p1 = query(w * 2, p, (p + k) / 2, pp, kk, tt), p2 = query(w * 2 + 1, (p + k) / 2 + 1, k, pp, kk, tt);
    if (w == 1)
    {
        if (DEBUG)
            cout << p1 + p2 << '\n';
    }
    return (p1 + p2) % mod;
}

void setw(int w, long long wr, int tt)
{
    w += S - 1;
    while (w)
    {
        sc[w][tt] += wr;
        sc[w][tt] %= mod;
        w /= 2;
    }
}

long long wr[300005];
int kop[300005];
long long dp[300005];
int main()
{
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    long long pref = 0;
    vector<pair<long long, long long>> v;
    for (int i = 1; i <= n; i++)
    {
        cin >> wr[i];
        pref += wr[i];
        v.push_back({pref % (mod), i});
    }
    if (n <= 3000)
    {
        dp[0] = 1;
        for (int i = 1; i <= n; i++)
        {
            long long sm = 0, sw = 0;
            for (int j = i; j; j--)
            {
                sm += wr[j];
                sm %= mod;
                if (!(sm % 2))
                    sw += dp[j - 1];
            }
            dp[i] = sw % mod;
        }
        cout << dp[n];
        return 0;
    }
    sort(v.begin(), v.end());
    int diff = 1, last = 0;
    for (auto i : v)
    {
        if (i.first != last)
            diff++;
        last = i.first;
        kop[i.second] = diff;
    }
    // for (int i = 1; i <= n; i++)
    // {
    //     cout << kop[i] << ' ';
    // }
    // cout << '\n';
    pref = 0;
    long long lw = 0;
    setw(1, 1, 0);
    for (int i = 1; i <= n; i++)
    {
        pref += wr[i];
        int ilop = (pref) % 2, ploi = (pref / (long long)(mod)) % 2;
        if (DEBUG)
            cout << ilop << ' ' << ploi << '\n';
        long long mw = query(1, 1, S, 1, kop[i], 2 * ilop + ploi) + query(1, 1, S, kop[i] + 1, diff + 2, 2 * ilop + ploi ^ 1);
        mw += query(1, 1, S, 1, kop[i], 2 * ilop + ploi ^ 3) + query(1, 1, S, kop[i] + 1, diff + 2, 2 * ilop + ploi ^ 2);
        mw %= mod;
        lw = mw;
        if (DEBUG)
            cout << i << ' ' << lw << '\n';
        setw(kop[i], mw, 2 * ilop + ploi);
    }
    cout << lw;
}