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#ifdef LOCAL
class SS {
   int x[0];
};
extern "C" SS __sanitizer_print_stack_trace();
#define __last_state                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   }                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   ;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   \
   SS x {                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              \
      __sanitizer_print_stack_trace()
#endif
#include <bits/stdc++.h>
#include <chrono>
#include <ext/pb_ds/assoc_container.hpp>
#include <math.h>
using namespace __gnu_pbds;
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> indexed_set; // find_by_order(x) <-returns x-th element   order_of_key(x) <- returns order of element x
// mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());uniform_int_distribution<int> distr(0, 1e9);auto my_rand = bind(distr, gen); // my_rand() zwraca teraz liczbe z przedzialu [a, b]
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...) ;
#endif

#define int long long
const int MAXN = 500;
const int MAXA = 2e4;

struct arr {
   static const int MAXT = 3 * MAXN * MAXA;
   array<int32_t, 2 * MAXT + 10> arr{};
   auto &operator[](int x) { return arr[x + MAXT]; }
};

int jeden_(vector<int> &X) { return count(all(X), 0); }
int dwa_(vector<int> &X) {
   arr A;
   //    debug(X);
   int res = 0;
   for (int x : X)
      A[2 * x]++;

   for (int x : X) {
      A[2 * x]--;
      res += A[-x];
      A[2 * x]++;
   }
   return res;
}

int32_t main() {
   _upgrade;
   int n;
   cin >> n;
   vector<int> X(n + 1);
   rep(i, n) {
      X[i + 1] = rand() % MAXA;
      cin >> X[i + 1];
   }
   partial_sum(all(X), X.begin());
   //    debug(X);

   auto get = [&](int i, int j) {
      assert(i <= j);
      return X[j + 1] - X[i];
   };

   vector<int> Y;
   rep(j, n) rep(i, j + 1) Y.push_back(get(i, j));
   //    debug(Y);

   arr A;
   int jeden = jeden_(Y);
   int dwa = dwa_(Y);
   int trzy = 0;
   rep(l, n) {
      rep(j, n) rep(i, j + 1) A[get(i, j) - X[l]]++;
      rep(j, n) rep(i, j + 1) trzy += A[-(get(i, j) + X[l + 1])];
   }
   debug(jeden, dwa, trzy);
   trzy -= jeden + 3 * dwa;
   assert(trzy % 6 == 0);
   trzy /= 6;
   cout << trzy << endl;
}