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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef pair<ld, ld> PLD;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<VL> VVL;
typedef vector<VII> VVII;
typedef vector<PLL> VLL;
typedef vector<VLL> VVLL;
typedef vector<VI> VVI;
typedef vector<VL> VVL;
typedef vector<bool> VB;
typedef map<int, int> MII;
typedef unordered_map<int, int> UMII;
typedef map<ll, ll> MLL;
typedef unordered_map<ll, ll> UMLL;

template <class T, class G>
ostream &operator<<(ostream &os, const pair<T, G> &para) {
  os << para.first << " " << para.second;
  return os;
}
template <class T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  for (const T &el : vec)
    os << el << " ";
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &vec) {
  for (const T &el : vec)
    os << el << " ";
  return os;
}

#define REP(i, j) for (int i = 0; i < j; i++)
#define REP1(i, j) for (int i = 1; i < j; i++)
#define FOREACH(el, n) for (auto &el : n)
#define LAST(x) (x[(int)x.size() - 1])
#define pb push_back
#define pf push_front
#define st first
#define nd second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define get_unique(x) x.erase(unique(all(x)), x.end());
#define sp ' '
#define ent '\n'

struct FenwickTree {
  VL bit;
  ll n;

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

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

  ll sum(ll l, ll r) { return sum(r) - sum(l - 1); }

  void add(ll idx, ll delta) {
    for (; idx < n; idx = idx | (idx + 1))
      bit[idx] += delta;
  }
};

const ll N = 300010;

FenwickTree good = FenwickTree(N);
FenwickTree bad = FenwickTree(N);

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

  int t = 1;
  // cin >> t;
  while (t--) {
    ll n;
    cin >> n;
    VL v;
    VL pref = {0};
    ll mod = 1e9 + 7;
    unordered_map<ll, ll> to_index;
    REP(i, n) {
      ll a;
      cin >> a;
      v.pb(a);
      pref.pb((pref.back() + a) % mod);
    }
    sort(all(pref));
    get_unique(pref);
    ll index = 1;
    FOREACH(el, pref) {
      to_index[el] = index;
      index++;
    }
    ll sum = 0;
    ll cnt = 0;
    REP(i, n) {
      sum += v[i];
      ll r = sum % mod;
      if (r & 1LL) {
        ll pom =
            (bad.sum(to_index[r]) + good.sum(to_index[r] + 1, N - 1)) % mod;
        if (i == n - 1) {
          cout << pom;
          return 0;
        }
        bad.add(to_index[r], pom);
      } else {
        ll pom =
            (good.sum(to_index[r]) + bad.sum(to_index[r] + 1, N - 1) + 1LL) %
            mod;
        if (i == n - 1) {
          cout << pom;
          return 0;
        }
        good.add(to_index[r], pom);
      }
    }
  }

  return 0;
}