#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, a, sum = 0, p = 0, res = 0;
  map<long long, long long> m;
  cin >> n;
  m[0] = 1;
  for (long long i = 1; i <= n; i++) {
    cin >> a;
    sum += a;
    p = max(p, m[sum]);
    res += i - p;
    m[sum] = i + 1;
  }
  cout << res;
}
