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#define make_pair mp
#define emplace_back pb
#include <bits/stdc++.h>
using namespace std;
mt19937 mt_rand(time(0));
const int N = 3e5 + 5, MOD = 1e9 + 7, D = 1e6 + 5, pods = (1<<19) - 1;
int n, tab[N], d[D][2];
map<int, int> m;

void add(int x, int id, int val) {
    x += pods;
    while(x != 0) {
        d[x][id] = (d[x][id] + val) % MOD;
        x /= 2;
    }
}

int sum(int x, int y, int id) {
    if(x > y) return 0;
    x += pods;
    y += pods;
    int res = d[x][id];
    if(x != y) res = (res + d[y][id]) % MOD;
    while(x / 2 != y / 2) {
        if(x % 2 == 0) res = (res + d[x+1][id]) % MOD;
        if(y % 2 == 1) res = (res + d[y-1][id]) % MOD;
        x /= 2;
        y /= 2;
    }
    return res;
}

int main() {
	scanf("%d", &n);
    m[0] = 0;
    for(int i=1;i<=n;i++) {
        scanf("%d", &tab[i]);
        tab[i] = (tab[i-1] + tab[i]) % MOD;
        m[tab[i]] = 0;
    }
    int cnt = 0;
    for(auto k : m) {
        cnt++;
        m[k.first] += cnt;
    }
    add(m[0], 0, 1);
    for(int i=1;i<=n;i++) {
        int val = 0;
        int mm = m[tab[i]];
        if(tab[i] % 2 == 0) {
            val = (sum(1, mm, 0) + sum(mm+1,cnt,1)) % MOD;
            add(mm, 0, val);
        } else {
            val = (sum(1, mm, 1) + sum(mm+1,cnt,0)) % MOD;
            add(mm, 1, val);
        }
        if(i == n) printf("%d\n", val);
    }
	return 0;
}