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#include<bits/stdc++.h>
#define FOR(i,a,b) for(int i=a;i<b;++i)
#define FORD(i,a,b) for(int i=a;i>=b;--i)
#define PB push_back
#define EB emplace_back
#define FI first
#define SE second
#define umap unordered_map
#define uset unordered_set
#define vi vector<int>
#define vvi vector<vi>
#define vll vector<ll>
#define vvll vector<vll>
#define vpii vector<pii>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ALL(X) (X).begin(),(X).end()
#ifndef DEBUG
#define endl (char)10
#endif
using namespace std;
using ll = long long;
using ld = long double;

template <class T>
istream& operator>> (istream& is, vector<T>& vec){
    FOR(i,0,vec.size()) is >> vec[i];
    return is;
}
template <class T>
ostream& operator<< (ostream& os, vector<T>& vec){
    for(auto& t : vec) os << t << " ";
    return os;
}

const ll M = 1'000'000'007;

template<typename IntType>
struct BinaryIndexedTreeSum {
    int n;
    vector<IntType> elems;

    BinaryIndexedTreeSum(int n_){
        n = n_ + 1;
        elems.assign(n, 0);
    }

    void add(int idx, IntType v){
        idx++;
        while(idx < n){
            elems[idx] += v;
            if (elems[idx] >= M) elems[idx] %= M;
            idx += (idx & (-idx));
        }
    }

    IntType get(int idx) {
        return sum(idx, idx + 1);
    }

    // prefix sum of A[0], A[1], ..., A[idx - 1]
    IntType __prefix(int idx){
        IntType res = 0;
        while(idx > 0){
            res += elems[idx];
            if (res >= M) res %= M;
            idx ^= (idx & (-idx));
        }
        return res;
    }

    IntType sum(int l, int r){
        return (__prefix(r) - __prefix(l) + M) % M;
    }
};
using BitSum = BinaryIndexedTreeSum<int>;

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vi V(n);
    cin >> V;
    vi P(n + 1);
    P[0] = 0;
    FOR(i,0,n) P[i + 1] = (P[i] + V[i]) % M;
    vi E, O;
    FOR(i,0,n+1) {
        if(P[i] & 1) O.PB(P[i]);
        else E.PB(P[i]);
    }
    sort(ALL(O));
    sort(ALL(E));
    O.erase(unique(ALL(O)), O.end());
    E.erase(unique(ALL(E)), E.end());
    BitSum bso((int) O.size()), bse((int) E.size());
    bse.add(0, 1);
    int ans = 0;
    FOR(i,1,n+1){
        int x = P[i];
        if (x % 2 == 0){
            int xe = lower_bound(ALL(E), x) - E.begin();
            auto ye = lower_bound(ALL(O), x);
            ans = bse.sum(0, xe + 1);
            if (ye != O.end()) ans += bso.sum(ye - O.begin(), O.size());
            if (ans >= M) ans %= M;
            bse.add(xe, ans);
        } else {
            int xo = lower_bound(ALL(O), x) - O.begin();
            auto yo = lower_bound(ALL(E), x);
            ans = bso.sum(0, xo + 1);
            if (yo != E.end()) ans += bse.sum(yo - E.begin(), E.size());
            if (ans >= M) ans %= M;
            bso.add(xo, ans);
        }
    }
    cout << ans << endl;
}