#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
const int MAX = 510000;
const int MOD = 1000000007;
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}
long long COM(int n, int k) {
  if (n < k) return 0;
  if (n < 0 || k < 0) return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
int main() {
  ll n;
  cin >> n;
  ll a[n];
  for (int i = 0; i <= n - 1; i++) cin >> a[i];
  ll b[n + 1];
  b[0] = 0;
  map<ll, ll> m;
  ++m[0];
  ll ans = 0;
  for (int i = 1; i <= n; i++) {
    b[i] = b[i - 1] + a[i - 1];
    ++m[b[i]];
  }
  sort(b, b + n + 1);
  for (auto i : m) {
    if (i.second > 1) {
      COMinit();
      ans += COM(i.second, 2);
    }
  }
  cout << ans << endl;
}
