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// Arti1990, II UWr

#include <bits/stdc++.h>

#define forr(i, n)                  for(int i=0; i<n; i++)
#define FOREACH(iter, coll)         for(auto iter = coll.begin(); iter != coll.end(); ++iter)
#define FOREACHR(iter, coll)        for(auto iter = coll.rbegin(); iter != coll.rend(); ++iter)
#define lbound(P,K,FUN)             ({auto SSS=P, PPP = P-1, KKK=(K)+1; while(PPP+1!=KKK) {SSS = (PPP+(KKK-PPP)/2); if(FUN(SSS)) KKK = SSS; else PPP = SSS;} PPP;})
#define testy()                     int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests)
#define CLEAR(tab)                  memset(tab, 0, sizeof(tab))
#define CONTAIN(el, coll)           (coll.find(el) != coll.end())
#define FOR(i, a, b)                for(int i=a; i<=b; i++)
#define FORD(i, a, b)               for(int i=a; i>=b; i--)
#define MP                          make_pair
#define PB                          push_back
#define ff                          first
#define ss                          second
#define deb(X)                      X;

#define M  1000000007
#define M2 2000000014
#define INF 1000000007LL

using namespace std;

int n, m, a, S = 1;
long long d[2][2100007];
long long tab[1000007];
map <long long, long long> mapa;

int parz(long long nr)
{
    return nr%2;
    /*nr %= M2;
    if(nr < M)
        return nr%2;
    else
        return (nr-M)%2;*/
}

void wkladaj(bool b, int nr, long long ile)
{
//    cout << "wklada " << ile << " na pozycji " << nr << " w " << b << endl;
    nr += S;
    while(nr > 0)
    {
        d[b][nr] += ile;
        d[b][nr] %= M;
        nr >>= 1;
    }
}

long long licz_lewo(bool b, int nr)
{
//    cout << "zlicza elementy na lewo od " << nr << " w " << b << endl;
    nr += S;
    long long res = 0;//d[b][nr];
    while(nr > 1)
    {
        if(nr&1)
        {
            res += d[b][nr-1];
        }
        nr >>= 1;
    }
//    cout << "wyszlo " << res << endl;
    return res % M;
}

long long policz(long long nr)
{
    bool b = parz(nr);
    long long kon = mapa.lower_bound((nr+1)%M2)->ss, pocz = mapa.lower_bound((nr+M+1)%M2)->ss;
//    cout << "od " << (nr+M+1)%M2 << " do " << (nr+1)%M2 << " na parzystosci " << b << endl;
//    cout << "pocz: " << pocz << ", kon: " << kon << endl;
    if(pocz < kon)
    {
        return (licz_lewo(b, kon) - licz_lewo(b, pocz) + d[1-b][1] + licz_lewo(1-b, pocz) - licz_lewo(1-b, kon)  +M+M+M)%M;
    }
    else // kon < pocz
    {
        return (d[b][1] + licz_lewo(b, kon) - licz_lewo(b, pocz) + licz_lewo(1-b, pocz) - licz_lewo(1-b, kon)   +M+M+M)%M;
    }
}

int solve()
{
    scanf("%d", &n);
    mapa[0] = 1;
    mapa[M2+1] = 1;
    long long suma = 0;
    forr(i, n)
    {
        scanf("%d", &tab[i]);
        suma = (suma + tab[i]) % M2;
        tab[i] = suma;
        mapa[suma] = 1;
        mapa[(suma+1)%M2] = 1;
        mapa[(suma+M+1)%M2] = 1;

    }
    while(S < mapa.size()+5)
        S *= 2;
    int il = 1;
    FOREACH(it, mapa)
    {
        it->second = il++;
//        cout << (it->ff) << " idzie na " << (it->ss) << endl;
    }
    wkladaj(0, mapa[0], 1);

    long long res = 0;
    forr(i, n)
    {
        res = policz(tab[i]);
        res %= M;
        wkladaj(parz(tab[i]), mapa[tab[i]], res);
//        cout << tab[i] << " ma res " << res << endl;
    }
    printf("%lld\n", res);

    return 0;
}

int main()
{
    solve();

    return 0;
}