#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  vector<long long> v(N + 1, 0);
  map<long long, long long> m;
  m[0]++;
  for (int i = 0; i < N; i++) {
    cin >> v[i + 1];
    v[i + 1] += v[i];
    m[v[i + 1]]++;
  }
  long long res = 0;
  for (auto x : m) {
    res += x.second * (x.second - 1) / 2;
  }
  cout << res << endl;
}
