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#include <cstdio>
#include <vector>
#include <unordered_set>
#include <map>
#include <algorithm>

using namespace std;

int main() {
  int n;
  vector<long long> sums;

  scanf("%d", &n);

  vector<int> a(n);

  for (int i = 0; i < n; i++) {
    scanf("%d", &a[i]);
  }

  for (int i = 0; i < a.size(); i++) {
    long long sum = a[i];
    sums.push_back(sum);

    for (int j = i + 1; j < a.size(); j++) {
      sum += a[j];
      sums.push_back(sum);
    }
  }

  unsigned long long result = 0;

  for (int i = 0; i < sums.size(); i++) {
    map<long long, long long> seen;

    for (int j = i + 1; j < sums.size(); j++) {
      if (seen.contains(-(sums[i] + sums[j]))) {
        result += seen[-(sums[i] + sums[j])];
      }

      if (seen.contains(sums[j])) {
        seen[sums[j]]++;
      }
      else {
        seen[sums[j]] = 1;
      }
    }
  }

  printf("%llu\n", result);

  return 0;
}