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#include <bits/stdc++.h>

#define fi first
#define se second
#define p_b push_back
#define pll pair<ll,ll>
#define pii pair<int,int>
#define m_p make_pair
#define all(x) x.begin(),x.end()
#define sset ordered_set
#define sqr(x) (x)*(x)
#define pw(x) (1ll << (x))
#define sz(x) (int)x.size()
#define fout(x) {cout << x << "\n"; return; }

using namespace std;
typedef long long ll;
typedef long double ld;
const int MAXN = 1e5;
const int M = pw(16);
const long long mod = 1e9 + 7;
const int N = 5e5;
const ll inf = 1e18;
template <typename T> void vout(T s){cout << s << endl;exit(0);}

void u(int &x, int a){
    x += a;
    if(x >= mod){
         x -= mod;       
    }
}

struct node{
    int sum;
    node *l, *r;
    node(): sum(0), l(r=nullptr) {}
};

int sumM(int a, int b){
    int r = a;
    u(r, b);
    return r;
}

node *rootE = new node(), *rootO = new node();

void modify(node *v, ll tl, ll tr, ll pos, int val){
    if(tl == tr) {
        u(v -> sum, val);
    }else{
        ll tm = (tl + tr) >> 1;
        if(pos <= tm){
            if(v -> l == nullptr) v -> l = new node();
            modify(v -> l, tl, tm, pos, val);
        }else{
            if(v -> r == nullptr) v -> r = new node();
            modify(v -> r, tm + 1, tr, pos, val);
        }
        v -> sum = 0;
        if(v -> l != nullptr) u(v -> sum, (v -> l) -> sum);
        if(v -> r != nullptr) u(v -> sum, (v -> r) -> sum);
    }
}

int get(node *v, ll tl, ll tr, ll l, ll r){
    if(l > r || v == nullptr) return 0;
    if(tl == l && tr == r){
        return v -> sum;        
    }
    ll tm = (tl + tr) >> 1;
    return sumM(get(v -> l, tl, tm, l, min(r, tm)), get(v -> r, tm + 1, tr, max(l, tm + 1), r));
}

void update(ll pos, ll val){
    if(pos % 2 == 0) modify(rootO, 0, 4 * mod - 1, pos, val);
    else modify(rootE, 0, 4 * mod - 1, pos, val);
    if(pos % 2 == 0)modify(rootO, 0, 4 * mod - 1, pos + 2 * mod, val);    
    else modify(rootE, 0, 4 * mod - 1, pos + 2 * mod, val);    
}

int get(ll l, ll r, ll xe){
    if(!xe){
        return get(rootO, 0, 4 * mod - 1, l, r);
    }else{
        return get(rootE, 0, 4 * mod - 1, l, r);
    }
}

void brute(vector <ll> a){
    int n = a.size();
    vector <int> dp(n + 1);
    dp[0] = 1;
    for(int i = 0; i < n; i++){
        ll s = 0;
        for(int j = i; j < n; j++){
            s += a[j];
            s %= 2 * mod;
            if(s < mod){
                if(s % 2 == 0) dp[j + 1] += dp[i];
            }else{
                if(s % 2) dp[j + 1] += dp[i];
            }
        }
    }
    cout << dp[n] << "\n";
}

int main(){

    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    vector <ll> a(n), dp(n);

    for(auto &i : a) cin >> i;

    //brute(a);

    ll s = 0;

    update(0, 1);
    s = 0;

    for(int i = 0; i < n; i++){
        s += a[i];
        if(s >= 2 * mod) s -= 2 * mod;
        ll a, b;
        dp[i] = sumM(get(s + 1, s + mod, (s + mod) % 2), get(s + mod + 1, s + 2 * mod, (s + 2 * mod) % 2));
        update(s, dp[i]);   
    }    

    cout << dp[n - 1] << "\n";


    return 0;
}