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//Author: Piotr Zielinski
#include<bits/stdc++.h>
using namespace std;

template<class C> C reversed(C c) {reverse(c.begin(),c.end()); return c;}
#define rep(i, n) for(int i=0;i<(int)(n);i++)
#define all(X) (X).begin(), (X).end()
#define mp make_pair
#define st first
#define nd second
typedef long long ll;
typedef pair<ll, bool> pll;

const int M = 1 << 20;
const ll MOD = 1e9 + 7;

struct PlusTree {
    vector<ll> data;
    PlusTree() {
        data.resize(2 * M);
    }

    void update(int x, ll v) {
        x += M;
        data[x] = v % MOD;

        while(x != 1) {
            x >>= 1;
            data[x] = (data[2 * x] + data[2 * x + 1]) % MOD;
        }
    }

    ll query(int a, int b) {
        a += M;
        b += M;
        ll res = data[a];

        if(a != b)
            res += data[b];

        res %= MOD;

        while(a / 2 != b / 2) {
            if((a & 1) ^ 1)   res += data[a + 1];
            if(b & 1)       res += data[b - 1];
            res %= MOD;
            a >>= 1; b >>= 1;
        }

        return res;
    }
};

struct Mop {
    ll rem;
    bool odd;
    int id;

    Mop() : rem(0), odd(false), id(0) {}

    bool operator<(const Mop& other) const {
        if(rem == other.rem)
            return id < other.id;

        return rem < other.rem;
    }
};

int32_t main(){
    ios::sync_with_stdio(false);
    int n;
    cin >> n;

    vector<ll> a(n);
    vector<Mop> sums(n + 1);
    for(int i = 0;i < n;++i) {
        cin >> a[i];
        sums[i + 1].rem = sums[i].rem + a[i];
        sums[i + 1].odd = sums[i].odd;
        sums[i + 1].id = i + 1;
        if(sums[i + 1].rem >= MOD) {
            sums[i + 1].rem -= MOD;
            sums[i + 1].odd = !sums[i + 1].odd;
        }
    }

    vector<Mop> sorted_sums = sums;
    sort(all(sorted_sums));

    vector<int> pos(n + 1);

    for(int i = 0;i <= n;++i) {
        pos[sorted_sums[i].id] = i;
    }

    PlusTree treeEven, treeOdd;
    ll res1, res2;

    treeEven.update(0, 1);
    // debug(pos);

    for(int i = 0;i < n;++i) {
        if(sums[i + 1].rem & 1) {
            res1 = treeOdd.query(0, pos[sums[i + 1].id] - 1);
            res2 = treeEven.query(pos[sums[i + 1].id] + 1, n + 1);
            treeOdd.update(pos[sums[i + 1].id], res1 + res2);
            // debug("ODD", res1, res2);

            // res1 = treeOdd.query(0, pos[sums[i + 1].id] - 1);
            // res2 = treeEven.query(pos[sums[i + 1].id] + 1, n + 1);
            // treeEven.update(pos[sums[i + 1].id], res1 + res2);
            // debug(res1, res2);
        }
        else {
            res1 = treeEven.query(0, pos[sums[i + 1].id] - 1);
            res2 = treeOdd.query(pos[sums[i + 1].id] + 1, n + 1);
            treeEven.update(pos[sums[i + 1].id], res1 + res2);
            // debug("EVEN", res1, res2);

            // res1 = treeOdd.query(0, pos[sums[i + 1].id] - 1);
            // res2 = treeEven.query(pos[sums[i + 1].id] + 1, n + 1);
            // treeOdd.update(pos[sums[i + 1].id], res1 + res2);
            // debug(res1, res2);
        }
    }

    if(sums[n].rem & 1)
        cout << treeOdd.query(pos[sums[n].id], pos[sums[n].id]) << "\n";
    else
        cout << treeEven.query(pos[sums[n].id], pos[sums[n].id]) << "\n";

    return 0;
}