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#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 2137
#endif

struct mp {
  array<int, 60000010> a, lst;
  int cnt = 0;

  int& operator[](int x) {
    x += 30000000;
    if (lst[x] != cnt) {
      a[x] = 0;
    }
    lst[x] = cnt;
    return a[x];
  }

  void clear() {
    cnt++;
  }
};

const int N = 505;
int n;
int s[N];
int m = 0;
mp cc, c;//, cj;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cin >> n;
  //n = 500;
  mt19937 rng(2137);
  for (int i = 0; i < n; i++) {
    int x;
    cin >> x;
    //x = true ? 20000 : -20000;//int(rng() % 40001) - 20000;
    s[i + 1] = s[i] + x;
  }
  ll ans = 0;
  for (int i = 0; i <= n; i++) {
    for (int j = i + 1; j <= n; j++) {
      cc[s[j] - s[i]]++;
    }
  }
  for (int i = 0; i <= n; i++) {
    c.clear();
    for (int j = 0; j < i; j++) {
      for (int k = j + 1; k < i; k++) {
        int x = s[i] - s[j];
        int y = s[i] - s[k];
        int z = -(x + y);
        ans += c[s[i] - z];
      }
      c[s[j]]++;
    }
  }
  c.clear();
  for (int i = 0; i <= n; i++) {
    //cj.clear();
    for (int j = 0; j < i; j++) {
      for (int k = j + 1; k < i; k++) {
        int x = s[i] - s[j];
        int y = s[i] - s[k];
        int z = -(x + y);
        // 3 takie same
        //ans += cj[s[i] - z];
        // 2 takie same
        ans += cc[z] - c[s[i] - z];
      }
      //cj[s[j]]++;
    }
    c[s[i]]++;
  }
  c.clear();
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < i; j++) {
      for (int k = 0; k <= i; k++) {
        c[-s[j] + s[i + 1] - s[k]]--;
      }
    }
    for (int j = 0; j < n; j++) {
      for (int k = max(j, i + 1); k < n; k++) {
        c[-s[i] + s[k + 1] - s[j]]++;
      }
    }
    for (int j = 0; j < i; j++) {
      for (int k = j; k < i; k++) {
        ans += c[-(s[i + 1] + s[k + 1] - s[j])];
      }
    }
  }
  cout << ans << '\n';
}