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#include <bits/stdc++.h>

using namespace std;

int n, p;

vector<vector<int>> tree;
vector<int> pos;
vector<int> sorted;
vector<int> v;

const int MOD = 1e9+7;

int sum(int b, int e, bool val, int l = 0, int r = (1 << p), int x = 1) {
    if (l >= r || l >= e || r <= b)
        return 0;
    if (l >= b && r <= e)
        return tree[x][val];
    int mid = (l + r + 1) >> 1;
    int ret = sum(b, e, val, l, mid, x << 1) + sum(b, e, val, mid, r, (x << 1) + 1);
    if (ret >= MOD)
        ret -= MOD;
    return ret;
}

void insert(int val, int pos, bool parity) {
    pos += (1 << p);
    while (pos) {
        tree[pos][parity] += val;
        if (tree[pos][parity] >= MOD)
            tree[pos][parity] -= MOD;
        pos >>= 1;
    }
}

int getDp(int i) {
    int mid = upper_bound(sorted.begin(), sorted.end(), v[i]) - sorted.begin();
    return sum(0, mid, v[i] & 1) + sum(mid, n, !(v[i] & 1)); 
}

void solve() {
    insert(1, pos[0], 0);
    int dp = 1;
    for (int i = 1; i < n; ++i) {
        dp = getDp(i);
        if (dp >= MOD)
            dp -= MOD;
        
        insert(dp, pos[i], v[i] & 1);
    }
    cout << dp << '\n';
}

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

    cin >> n;
    ++n;
    v.resize(n);
    v[0] = 0;
    for (int i = 1; i < n; ++i) {
        cin >> v[i];
        v[i] += v[i - 1];
        if (v[i] >= MOD)
            v[i] -= MOD;
    }
    
    pos.resize(n);
    for (int i = 0; i < n; ++i)
        pos[i] = i;
    sort(pos.begin(), pos.end(), [&](const int &a, const int &b) {
        return v[a] < v[b];
    });

    vector<int> tmp(n);
    for (int i = 0; i < n; ++i)
        tmp[pos[i]] = i;
    pos = tmp;

    sorted.resize(n);
    for (int i = 0; i < n; ++i)
        sorted[pos[i]] = v[i];

    p = 0;
    while ((1 << p) < n)
        ++p;
    tree.assign(1 << (p + 1), vector<int>(2, 0));

    solve();
}