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#include <iostream>
#include <cstdio>
#include <string>
#include <sstream> 
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <ctime>
#include <cassert>
using namespace std;

#define assert_range(x,a,b) assert((a) <= (x) and (x) <= (b))
const int MOD = 1e9+7;

struct SegmentTree {
    int M;
    vector<int> t;

    SegmentTree(int n) {
        M = 1;
        while (M <= n) {
            M *= 2;
        }
        t = vector<int>(2*M, 0);
    }

    void add(int x, int val) {
        x += M;
        t[x] += val;
        t[x] %= MOD;
        while (x > 1) {
            x /= 2;
            t[x] = t[2*x] + t[2*x+1];
            t[x] %= MOD;
        }
    }
    int sum(int x, int y) {
        if (x > y) return 0;
        x += M;
        y += M;
        int res = t[x];
        if (x != y) res += t[y];
        while (x/2 != y/2) {
            if (x%2 == 0) {
                res += t[x+1];
                res %= MOD;
            }
            if (y%2 == 1) {
                res += t[y-1];
                res %= MOD;
            }
            x /= 2;
            y /= 2;
        }
        return res;
    }
};

int main() {
    int n;
    scanf("%d", &n);
    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        scanf("%d", &a[i]);
    }
    set<int> rests = {0};
    int pref = 0;
    for (int i = 0; i < n; ++i) {
        pref += a[i];
        pref %= MOD;
        rests.insert(pref);
    }
    map<int, int> ord;
    int cur_ord = 0;
    for (auto it = rests.begin(); it != rests.end(); ++it) {
        ord[*it] = cur_ord;
        ++cur_ord;
    }
    auto evens = SegmentTree(rests.size()+10);
    auto odds = SegmentTree(rests.size()+10);
    evens.add(0, 1); // empty segment
    int r = 0;
    for (int i = 1; i <= n; ++i) {
        r = (r + a[i-1]) % MOD;
        int here = 0;
        int idx = ord[r];
        if (r % 2 == 0) {
            here = evens.sum(0, idx);
            here += odds.sum(idx+1, odds.M-1);
            here %= MOD;

            evens.add(idx, here);
        } else {
            here = odds.sum(0, idx);
            here += evens.sum(idx+1, odds.M-1);
            here %= MOD;

            odds.add(idx, here);
        }
        if (i == n) {
            printf("%d\n", here);
        }
    }

    return 0;
}