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#include <bits/stdc++.h>
using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())
template<class A, class B> auto& operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for(auto e : x) o << (", ")+2*!i++ << e; return o << '}';
}
ostream& operator<<(ostream &o, string &s) {
    return o << s.data();   
}
#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'
#else
#define debug(...) {}
#endif

constexpr int mod = (int) (1e9 + 7);

struct Tree {
    int pwr = 1;
    vector<int> t;

    Tree(int n) {
        while (pwr < n)
            pwr *= 2;
        t.resize(2 * pwr);
    }

    void add(int v, int val) {
        v += pwr - 1;
        while (v) {
            t[v] += val;
            t[v] %= mod;
            v /= 2;
        }
    }

    int sum(int v, int x, int y, int l, int r) {
        if (y < l || x > r)
            return 0;
        if (x >= l && y <= r)
            return t[v];
        return (sum(v * 2, x, (x + y) / 2, l, r) + 
                sum(v * 2 + 1, (x + y) / 2 + 1, y, l, r)) % mod;
    }

    int sum(int l, int r) {
        return sum(1, 1, pwr, l, r);
    }
};

int main() {
    cin.tie(0)->sync_with_stdio(0);

    int n;
    cin >> n;
    vector<int> a(n + 1), pref(n + 1);
    map<int, int> sc; 
    sc[0] = 0;

    FOR(i, 1, n) {
        cin >> a[i];
        pref[i] = (pref[i - 1] + a[i]) % mod;
        sc[pref[i]] = 0;
    }

    int cnt = 0;
    for (auto &[a, b] : sc)
        b = ++cnt;

    int m = ssize(sc);
    Tree even(m), odd(m);
    even.add(1, 1);
    int x, ans = 1;
    FOR(i, 1, n) {
        x = sc[pref[i]];
        if (pref[i] % 2 == 0) {
            ans = (even.sum(1, x) + odd.sum(x + 1, m)) % mod;
            even.add(x, ans);
        }
        else {
            ans = (odd.sum(1, x) + even.sum(x + 1, m)) % mod;
            odd.add(x, ans);
        }
    }
    cout << ans << '\n';

    return 0;
}