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

#pragma GCC maksuje_zadania_na_essie("pot200");
#define loop(i, a, b) for(ll i = a; i <= b; i++)
#define loop_rev(i, a, b) for(ll i = a; i >= b; i--)
#define all(x) x.begin(), x.end()
#define sz(x) int(x.size())
#define pb push_back

using ll = int64_t;

constexpr ll OFFSET = 20'000'000;

ll _cnt[2 * OFFSET + 1];
ll& cnt(ll sum) { return _cnt[sum + OFFSET]; }

ll _cnt2[2 * OFFSET + 1];
ll& cnt2(ll sum) { return _cnt2[sum + OFFSET]; }

constexpr ll MAX_N = 500 + 1;
ll arr[MAX_N], ps[MAX_N];

int main() {
  cin.tie(0)->sync_with_stdio(false);
  ll n; cin >> n;

  loop(i, 1, n) {
    cin >> arr[i];
    ps[i] = ps[i-1] + arr[i];
  }

  loop(i, 1, n) {
    loop(j, i, n) {
      loop(a, 1, n) {
        loop(b, a, n) {
          if(i == a && j == b) continue;
          ++cnt(ps[b] - ps[a-1] + ps[j] - ps[i-1]);
        }
      }
    }
  }

  ll res = 0;

  loop(i, 1, n) {
    loop(j, i, n) {
      res += cnt(ps[i-1] - ps[j]);
    }
  }

  loop(i, 1, n) {
    loop(j, i, n) {
      ++cnt2(ps[j] - ps[i-1]);
    }
  }

  loop(i, 1, n) {
    loop(j, i, n) {
      if(ps[j] - ps[i-1] == 0) {
        res -= 2 * (cnt2(0) - 1);
      }
      else {
        res -= 2 * cnt2(-2LL * (ps[j] - ps[i-1]));
      }
    }
  }

  cout << res / 6 << '\n';

}