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#include <bits/stdc++.h>

using namespace std;

const uint P = 1e9 + 7;

struct fenwick_tree
{
    size_t n;
    vector<uint64_t> F;
    uint64_t sum = 0;

    fenwick_tree(size_t m) : n(m), F(n+1) {}

    void delta(size_t p, uint64_t v)
    {
        sum += v;
        p++;
        while(p <= n)
            F[p] += v, p += p & -p;
    }
    uint64_t get_prefix(size_t p)
    {
        uint64_t r = 0;
        while(p)
            r += F[p], p &= p - 1;
        return r;
    }
    uint64_t get_suffix(size_t p) { return sum - get_prefix(p); }
};

int main()
{
    ios::sync_with_stdio(false); cin.tie(nullptr);

    size_t n;
    cin >> n;

    vector<uint> A(n);
    for(auto& a : A)
        cin >> a;

    vector<uint64_t> S(n+1);
    for(size_t i = 0; i < n; i++)
        S[i+1] = S[i] + A[i];

    map<uint, size_t> scale; scale[UINT_MAX];
    for(size_t i = 0; i <= n; i++) {
        const auto a = S[i] % P;
        const auto x = a == 0 ? 0 : P - a;
        scale[x];
    }
    size_t f = 0;
    for(auto& [k, v] : scale)
        v = f++;

    fenwick_tree xs[2] = {n, n};
    xs[0].delta(0, 1);

    uint64_t result;
    for(size_t i = 1; i <= n; i++) {
        const auto a = S[i] % P;

        const size_t l = scale.lower_bound(P - a)->second;
        uint64_t q = xs[a&1].get_prefix(l) + xs[(1^a)&1].get_suffix(l);

        const auto x = a == 0 ? 0 : P - a;
        xs[x % 2].delta(scale[x], result = q % P);
    }

    cout << result << endl;
}