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#include <cstdio>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>

typedef long long int i64;

int tab[505];
std::set<std::pair<int, int>> set;
std::unordered_map<int, int> map;
std::set<std::pair<int, int>> used;

inline void inc(std::unordered_map<int, int> &m, int k) {
  if (!m.contains(k)) {
    m[k] = 1;
  } else {
    ++m[k];
  }
}

inline int or_zero(std::unordered_map<int, int> &m, int k) { return m.contains(k) ? m[k] : 0; }

int main() {
  int N;
  scanf("%d", &N);
  for (int i = 0; i < N; ++i) {
    scanf("%d", &tab[i]);
    inc(map, tab[i]);
  }
  for (int i = 0; i < N; ++i) {
    int s = tab[i];
    for (int j = i + 1; j < N; ++j) {
      s += tab[j];
      inc(map, s);
    }
  }

  for (auto &p : map) {
    set.insert(p);
  }

  // for (auto &p : set) {
  //   printf("[%d, %d]  ", p.first, p.second);
  // }
  i64 res = 0;
  for (auto it = set.begin(); it != set.end() && it->first <= 0; ++it) {
    for (auto jt = it; jt != set.end(); ++jt) {
      if (jt == it) {
        if (it->first == 0) {
          if (it->second >= 3) {
            i64 n = it->second;
            res += n * (n - 1) * (n - 2) / 6;
          }
        } else if (it->second > 1) {
          i64 self = ((i64)it->second) * (it->second - 1) / 2;
          res += self * or_zero(map, -2 * it->first);
        }
      } else {
        int sum = it->first + jt->first;
        if (-sum < jt->first ) {
          break;
        }
        if (-sum != jt->first) {
          i64 them = ((i64)it->second) * jt->second;
          res += them * or_zero(map, -sum);
        } else {
          res += ((i64)it->second) * (jt->second) * (jt->second - 1) / 2;
        }
      }
    }
  }

  printf("%lld\n", res);
  return 0;
}