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#include <bits/stdc++.h>
#define ll long long

const int MAX_A = 4e7;

ll sum2[MAX_A + 10];
ll cnt_j[MAX_A + 10];

const int MID = 2e7 + 3;

void make_unique(std::vector<int> &v) {
  std::sort(v.begin(), v.end());
  v.erase(std::unique(v.begin(), v.end()), v.end());
}

int main() {
  std::ios_base::sync_with_stdio(0);
  std::cin.tie(NULL);

  int n;
  std::cin >> n;
  std::vector<int> w(n + 1);
  for (int i = 1; i <= n; i++)
    std::cin >> w[i];

  std::vector<int> p(n + 1, 0);
  for (int i = 1; i <= n; i++)
    p[i] = p[i - 1] + w[i];

  // std::unordered_map<int, int> sum2;
  std::vector<int> sum2vals;

  for (int i = 0; i <= n - 1; i++)
    for (int j = i + 1; j <= n; j++) {
      sum2[p[j] - p[i] + MID]++;
      sum2vals.push_back(p[j] - p[i]);
    }

  make_unique(sum2vals);

  ll res = 0;
  ll v;
  for (int i = n - 1; i >= 0; i--) {
    for (auto &k : sum2vals)
      cnt_j[k + p[i + 1] + MID] += sum2[k + MID];
    for (auto &k : sum2vals) {
      v = sum2[k + MID];
      if (v > 0)
        res += v * cnt_j[p[i] - k + MID];
    }
  }

  res -= sum2[0 + MID];

  for (auto k : sum2vals) {
    v = sum2[k + MID];
    if (k % 2 == 0) {
      if (k != 0) {
        res -= 3ll * v * sum2[(-k / 2) + MID];
      } else if (k == 0 && v > 0)
        res -= 3ll * v * (v - 1);
    }
  }

  std::cout << res / 6ll << "\n";
}