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#include <bits/stdc++.h>
using namespace std;

using ll = long long;

const int N = 3e5 + 7;
const int M = 1e9 + 7;
int as[N], xs[N];

int mod(int x, int a) {
    return (ll(x) + a) % M;
}

struct fenwick {
    void init(int n) {
        this->n = n;
        memset(s, 0, sizeof(s[0]) * (n+1));
    }

    void add(int v, int x) {
        for (++v; v <= n; v += (v & -v))
            s[v] = mod(s[v], x);
    }

    int query(int v) {
        int ans = 0;
        for (++v; v; v -= (v & -v))
            ans = mod(ans, s[v]);
        return ans;
    }
    
    int query(int l, int r) {
        return ((query(r) - query(l - 1)) % M + M) % M;
    }
    
    int n;
    int s[N];
} t[2][2];

int main() {
    int n;
    scanf("%d", &n);
    for (int i = 0; i < n; ++i) {
        scanf("%d", &as[i]);
        xs[i + 1] = mod(xs[i], as[i]);
    }

    sort(xs, xs + n+1);
    int e = unique(xs, xs + n+1) - xs;
    for (int i = 0; i < 2; ++i)
        for (int j = 0; j < 2; ++j)
            t[i][j].init(e);

    t[0][0].add(0, 1);
    
    int x = 0, m = 0, b = 0, dp;
    for (int i = 0; i < n; ++i) {
        int a = as[i];

        b ^= a & 1;
        if ((m += a) >= M) {
            x ^= 1;
            m -= M;
        }

        int l = lower_bound(xs, xs + e, m) - xs;

        dp = t[x][b].query(0, l);
        dp = mod(dp, t[x ^ 1][b].query(l+1, e-1));
        dp = mod(dp, t[x][b ^ 1].query(l+1, e-1));
        dp = mod(dp, t[x ^ 1][b ^ 1].query(0, l));
        
        t[x][b].add(l, dp);
    }

    printf("%d", dp);

    return 0;
}