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#include <iostream>
#include <unordered_map>
#include <vector>

int main() {
	int n; std::cin >> n;
	std::vector< int > uc(n);
	std::vector< int > buc;
	std::unordered_map< int, int > trzecia;

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

	for (int i = 0; i < n; ++i) {
		int suma = 0;
		for (int k = i; k < n; ++k) {
			suma += uc[k];
			buc.push_back(suma);
			trzecia[suma] += 1;
		}
	}

	int wynik = 0;

	for (int i =  0; i < buc.size(); ++i) {
		for (int j =  i + 1; j < buc.size(); ++j) {
			int suma = buc[i] + buc[j];

			auto it = trzecia.find(-suma);

			if (it == trzecia.end()) continue;

			int delta = it->second;

			if (it->first == buc[i]) { delta -= 1; };
			if (it->first == buc[j]) { delta -= 1; };

			wynik += delta;
		}
	}

	std::cout << (wynik/3) << "\n";;
}