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#include <iostream>
#include <map>
#include <vector>
using namespace std;
long twofromn(int n) {
  return (((long)n) * (n - 1)) / 2;
}
long threefromn(int n) {
  long result = 0;
  while (n) {
    --n;
    result += ((long)n) * (n - 1);
  }
  return result / 2;
}
long sum2count(map< int, int > const &m, int value) {
  long result = 0;
  map< int, int >::const_iterator beg = m.begin();
  while (beg != m.end() && beg->first < value) {
    map< int, int >::const_iterator end = m.lower_bound(value - beg->first);
    if (end != m.end()) {
      if (end->first < beg->first)
        break;
      if (beg->first + end->first == value) {
        if (end->first == beg->first) {
          result += twofromn(beg->second);
          break;
        }
        result += ((long)(beg->second)) * end->second;
      }
    }
    ++beg;
  }
  return result;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  vector< int > a(n);
  for (int i = 0; i < n; cin >> a[i++]) {
  }
  map< int, int > pos, neg;
  int zero_count = 0;
  for (int i = 0; i < n; i++) {
    int c = 0;
    for (int j = i; j < n; j++)
      if (c += a[j])
        if (c < 0)
          neg[-c]++;
        else
          pos[c]++;
      else
        ++zero_count;
  }
  long result = threefromn(zero_count);
  while (neg.size() && pos.size()) {
    map< int, int >::iterator neg_it = --neg.end(), pos_it = --pos.end();
    if (neg_it->first == pos_it->first)
      result += (long)zero_count * neg_it->second * pos_it->second;
    if (neg_it->first > pos_it->first) {
      result += sum2count(pos, neg_it->first) * neg_it->second;
      neg.erase(neg_it);
    } else {
      result += sum2count(neg, pos_it->first) * pos_it->second;
      pos.erase(pos_it);
    }
  }
  cout << result << '\n';
}