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// Daniel Grzegorzewski
// while (clock()<=69*CLOCKS_PER_SEC)
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")

#define MP make_pair
#define PB push_back
#define ST first
#define ND second

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

//X.find_by_order(k); - zwraca iterator na k-ty element (numeracja od zerowego)
//X.order_of_key(k); - zwraca liczbę elementów ostro mniejszych niż k

typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef long long LL;

void init_ios() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
}
 
const uint64_t SEED = chrono::steady_clock::now().time_since_epoch().count();
mt19937_64 rng(SEED);

const int N = 503;
const int K = 2*(int)1e7 + 2;

int n, a[N], cnt[2*K];
VI vals;
LL res;

int main() {
  init_ios();
  cin >> n;
  for (int i = 1; i <= n; ++i)
    cin >> a[i];
  for (int i = 1; i <= n; ++i) {
    int tmp = 0;
    for (int j = i; j <= n; ++j) {
      tmp += a[j];
      if (cnt[tmp+K] == 0)
        vals.PB(tmp);
      ++cnt[tmp+K];
    }
  }
  sort(vals.begin(), vals.end());
  for (int i = 0; i < (int)vals.size(); ++i) {
    int v1 = vals[i];
    if (v1 == 0) {
      res += (1LL)*cnt[K]*(cnt[K]-1)*(cnt[K]-2)/6;
      continue;
    }
    if (cnt[K-2*v1] > 0)
      res += (1LL)*cnt[v1+K]*(cnt[v1+K]-1)/2*cnt[K-2*v1];
    for (int j = i+1; j < (int)vals.size() && -v1 > 2*vals[j]; ++j)
      res += (1LL)*cnt[v1+K]*cnt[vals[j]+K]*cnt[K-v1-vals[j]];
  }
  cout<<res<<"\n";
}