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#include <iostream>
#include <vector>
#include <unordered_map>
#include <numeric>
#include <algorithm>

using namespace std;

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n;
	cin >> n;
	vector<int> uc(n);

	for (int i = 0; i < n; i++) {
		cin >> uc[i];
	}

	vector<int> buc;

	for (int l = 1; l < uc.size() + 1; l++) {
		for (int i = 0; i < uc.size() + 1 - l; i++) {
			buc.push_back(accumulate(uc.begin() + i, uc.begin() + i + l, decltype(uc)::value_type(0)));
		}
	}


	//sort(buc.begin(), buc.end());

	int res = 0;

	for (int i = 0; i < buc.size(); i++) {
		//cout << buc[i] << " " ;

		unordered_map<int, int> count;
		for (int j = 0; j < buc.size(); j++) {
			if (j == i)
				continue;
			count[-buc[j] - buc[i]]++;
		}

		for (int j = 0; j < buc.size(); j++) {
			if (j == i)
				continue;
			if (-buc[i] == 2 * buc[j]) {
				res += count[buc[j]] - 1;
			}
			else {
				res += count[buc[j]];
			}
		}

	}

	cout << res / 6 << endl;
}