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#include <bits/stdc++.h>
#include <random>
#define ll long long int
#define pb push_back
#define st first
#define nd second
#define pii pair<int,int>
#define mp make_pair
#define pll pair<long long,long long>
#define ld long double
#define ull unsigned long long

using namespace std;

const int mod = 1e9 + 7;
const int nax = 3e5 + 5;
ll a[nax];
set<int> UNIQ;
ll pref[nax];
int n;


struct FenwickTree {
    vector<int> bit;  // binary indexed tree
    int n;

    FenwickTree(int n) {
        this->n = n;
        bit.assign(n, 0);
    }

    FenwickTree(vector<int> a) : FenwickTree(a.size()) {
        for (size_t i = 0; i < a.size(); i++)
            add(i, a[i]);
    }

    int sum(int r) {
        int ret = 0;
        for (; r >= 0; r = (r & (r + 1)) - 1){
            ret += bit[r];
            if(ret >= mod) ret -= mod;
        }
        return ret;
    }

    int sum(int l, int r) {
        if(l > r) return 0;
        int res = sum(r) - sum(l - 1);
        if(res < 0) res += mod;
        return res;
    }

    void add(int idx, int delta) {
        for (; idx < n; idx = idx | (idx + 1)){
             bit[idx] += delta;
             if(bit[idx] >= mod) bit[idx] -= mod;
        }
    }
};

vector<int> u;

int get(int x){
    return (int)(lower_bound(u.begin(), u.end(), x) - u.begin());
}

ll dp[nax];

void solve(){
    cin >> n;
    for(int i=1;i<=n;i++) cin >> a[i];
    for(int i=1;i<=n;i++) pref[i] = pref[i - 1] + a[i];
    for(int i=0;i<=n;i++) UNIQ.insert(pref[i] % mod);
    UNIQ.insert(mod - 1);
    for(int x : UNIQ) u.pb(x);
    FenwickTree treeNP(nax), treeP(nax);
    treeP.add(get(0), 1);
    for(int i=1;i<=n;i++){
        ll cur = pref[i] % mod;
        int s1 = 0;
        int s2 = 0;
        if(cur & 1){
            s1 = treeNP.sum(0, get(cur));
            s2 = treeP.sum(get(cur), get(mod - 1));
        }
        else{
            s1 = treeP.sum(0, get(cur));
            s2 = treeNP.sum(get(cur), get(mod - 1));
        }

        dp[i] = (s1 + s2) % mod;
        if(cur & 1) treeNP.add(get(cur), dp[i]);
        else treeP.add(get(cur), dp[i]);
    }
    cout << dp[n];
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    int tt = 1;
    // cin >> tt;
    while(tt--) solve();

    return 0;
}