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#include <bits/stdc++.h>
using namespace std;
const int B = 1 << 19;
const int N = 300001;
const long long MOD = 1e9 + 7;
long long n, a, d[2 * B + 1][2];
long long preft[N];
map<long long, int> pref_to_ind;
vector<long long>v;

void add(int a, long long k, int p) {
  a += B;
  while (a > 1) {
    d[a][p] += k;
    d[a][p] %= MOD;
    a >>= 1;
  }
}

long long leq(int a, int p) {
  a += B;
  long long sum = d[a][p];
  while (a > 1) {
    if (a % 2) {
      sum += d[a - 1][p];
      sum %= MOD;
    }
    a >>= 1;
  }
  return sum;
}

long long gr(int a, int p) {
  a += B;
  long long sum = 0;
  while (a > 1) {
    if (a % 2 == 0) {
      sum += d[a + 1][p];
      sum %= MOD;
    }
    a >>= 1;
  }
  return sum;
}

int main()
{
  ios_base::sync_with_stdio(0);

  cin >> n;
  add(0, 1, 0);
  v.push_back(0);

  long long pref = 0;
  long long m = 0;
  long long res = 0;
  for (int i = 1; i <= n; i++) {
    cin >> a;
    pref += a;
    pref %= MOD;
    preft[i] = pref;
    v.push_back(pref);
  }

  sort(v.begin(), v.end());

  int ind = 0;
  pref_to_ind[v[0]] = 0;
  for (int i = 1; i < v.size(); i++) {
    if (v[i] != v[i  - 1]) {
      ind++;
      pref_to_ind[v[i]] = ind;
    }
  }

  for (int i = 1; i <= n; i++) {
    int p = preft[i] % 2;;
    int pref_ind = pref_to_ind[preft[i]];
    res = (leq(pref_ind, p) + gr(pref_ind, (p + 1) % 2)) % MOD;
    add(pref_ind, res, p);
  }
  cout << res << endl;

  return 0;
}