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#include <iostream>
#include <vector>
#include <algorithm>
#include <map>

using namespace std;

typedef long long ll;

const ll MOD = 1000000007;
vector< map<ll, ll> > M(2);

vector<ll> T0, T1;
ll l, Size;

void Mapuj(vector< vector<ll> >& a)
{
    for (int i = 0; i < 2; ++i)
    {
        sort(a[i].begin(), a[i].end());
        ll akt = 0;
        for (int j = 0; j < a[i].size(); ++j)
        {
            if (j == 0 || a[i][j] != a[i][j - 1])
            {
                M[i][a[i][j]] = akt;
                ++akt;
            }
        }
    }
}

void Stworz(vector<ll>& T, int n)
{
    int p = 1;
    while (p < n)
        p *= 2;
    l = p;
    Size = 2 * p - 1;
    for (int i = 0; i <= Size; ++i)
        T.push_back(0);
}

void Dodaj(vector<ll>& T, int a, ll x)
{
    a += l;
    while (a != 0)
    {
        T[a] = (T[a] + x) % MOD;
        a /= 2;
    }
}

ll Sum(vector<ll>& T, int a, int b)
{
    a += l;
    b += l;
    ll s = T[a];
    if (a != b)
        s = (s + T[b]) % MOD;
    while (a / 2 != b / 2)
    {
        if (a % 2 == 0)
            s = (s + T[a + 1]) % MOD;
        if (b % 2 == 1)
            s = (s + T[b - 1]) % MOD;
        a /= 2;
        b /= 2;
    }
    return s;
}

int Szukaj1(vector<ll>& a, ll x)
{
    int l = 0, p = a.size() - 1, s, r = -1;
    while (l <= p)
    {
        s = (l + p) / 2;
        if (a[s] >= x)
        {
            r = s;
            p = s - 1;
        }
        else
            l = s + 1;
    }
    return r;
}

int main()
{
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    vector<ll> a(n);
    ll pref = 0;
    vector< vector<ll> > resz(2);
    for (int i = 0; i < n; ++i)
    {
        cin >> a[i];
        pref = (pref + a[i]) % MOD;
        resz[pref % 2].push_back(pref);
    }
    Mapuj(resz);
    Stworz(T0, 300000);
    Stworz(T1, 300000);
    vector<ll> dp(n);
    pref = 0;
    for (int i = 0; i < n; ++i)
    {
        pref = (pref + a[i]) % MOD;
        if (pref % 2 == 0)
        {
            int gdzie = Szukaj1(resz[1], pref + 1);
            dp[i] = (Sum(T0, 0, M[0][pref]) + 1) % MOD;
            if (gdzie != -1)
                dp[i] = (dp[i] + Sum(T1, M[1][resz[1][gdzie]], Size - l)) % MOD;
            Dodaj(T0, M[0][pref], dp[i]);
        }
        else
        {
            int gdzie = Szukaj1(resz[0], pref + 1);
            dp[i] = Sum(T1, 0, M[1][pref]);
            if (gdzie != -1)
                dp[i] = (dp[i] + Sum(T0, M[0][resz[0][gdzie]], Size - l)) % MOD;
            Dodaj(T1, M[1][pref], dp[i]);
        }
    }
    cout << dp[n - 1];
    return 0;
}