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#include <bits/stdc++.h>

using namespace std;

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define reunique(v) v.resize(std::unique(v.begin(), v.end()) - v.begin())
#define sz(v) ((int)(v).size())

#define vec1d(x) vector<x>
#define vec2d(x) vector<vec1d(x)>
#define vec3d(x) vector<vec2d(x)>
#define vec4d(x) vector<vec3d(x)>

#define ivec1d(x, n, v) vec1d(x)(n, v)
#define ivec2d(x, n, m, v) vec2d(x)(n, ivec1d(x, m, v))
#define ivec3d(x, n, m, k, v) vec3d(x)(n, ivec2d(x, m, k, v))
#define ivec4d(x, n, m, k, l, v) vec4d(x)(n, ivec3d(x, m, k, l, v))

#ifdef LOCAL
#include "pretty_print.h"
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: ", debug_out(__VA_ARGS__)
#else
#define dbg(...) 42
#endif

#define nl "\n"

typedef long double ld;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;

template <typename T> T sqr(T x) { return x * x; }
template <typename T> T abs(T x) { return x < 0? -x : x; }
template <typename T> T gcd(T a, T b) { return b? gcd(b, a % b) : a; }
template <typename T> bool chmin(T &x, const T& y) { if (x > y) { x = y; return true; } return false; }
template <typename T> bool chmax(T &x, const T& y) { if (x < y) { x = y; return true; } return false; }

auto random_address = [] { char *p = new char; delete p; return (uint64_t) p; };
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1));
mt19937_64 rngll(chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1));

const int MOD = 1e+9 + 7;
#define int long long

void addmod(int& x, int d) {
    x += d;
    if (x >= MOD) {
        x -= MOD;
    } else if (x < 0) {
        x += MOD;
    }
}

struct TFenwick {
    int n;
    vector<int> s;

    TFenwick(int n) : n(n) {
        s.resize(n + 1, 0);
    }

    void upd(int x, int d) {
        for (int i = x + 1; i <= n; i += i & -i) {
            addmod(s[i], d);
        }
    }

    int sum(int l, int r) {
        if (l > r) {
            return 0;
        }
        if (l) {
            int ret = sum(0, r);
            addmod(ret, -sum(0, l - 1));
            return ret;
        }
        int ret = 0;
        for (int i = r + 1; 1 <= i; i -= i & -i) {
            addmod(ret, s[i]);
        }
        return ret;
    }
};

int32_t main(int /* argc */, const char** /* argv */)
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
#ifdef LOCAL
    assert(freopen("i.txt", "r", stdin));
    assert(freopen("o.txt", "w", stdout));
#endif

    int n;
    cin >> n;
    vector<int> v = {0};
    for (int i = 0; i < n; ++i) {
        int x;
        cin >> x;
        v.push_back((v.back() + x) % MOD);
    }
    auto x = v;
    sort(all(x));
    reunique(x);
    int m = sz(x);
    TFenwick even(m);
    TFenwick odd(m);
    even.upd(0, 1);

    int f = 0;
    // vector<int> g(n + 1);
    // g[0] = 1;

    for (int i = 1; i <= n; ++i) {
        int idx = lower_bound(all(x), v[i]) - x.begin();
        f = 0;
        if (v[i] & 1) {
            addmod(f, odd.sum(0, idx));
            addmod(f, even.sum(idx + 1, m - 1));
            odd.upd(idx, f);
        } else {
            addmod(f, even.sum(0, idx));
            addmod(f, odd.sum(idx + 1, m - 1));
            even.upd(idx, f);
        }

        // for (int j = 0; j < i; ++j) {
        //     if (((v[i] - v[j] + MOD) % MOD) % 2 == 0) {
        //         addmod(g[i], g[j]);
        //     }
        // }
    }
    cout << f << nl;

#ifdef LOCAL
    cerr << "Time execute: " << clock() / (double)CLOCKS_PER_SEC << " sec" << endl;
#endif
    return 0;
}