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#include <cstdio>
#include <cstdint>
#include <vector>
#include <map>

using namespace std;

const int MAX = 500 * 20016 * 4;

int main () {
	int n;
	scanf("%d", &n);
	vector<int> ucb;
	for (int i = 0; i < n; ++i) {
		int x;
		scanf("%d", &x);
		ucb.push_back(x);
	}
	vector<int> P;
	P.push_back(0);
	for (int i = 0; i < n; ++i) {
		P.push_back(P[i] + ucb[i]);
	}
	vector<int64_t> counts(2 * MAX, 0);
	int64_t res = 0;
	for (int c = 0; c <= n; ++c) {
		for (int b = 0; b <= n; ++b) {
			for (int a = b + 1; a <= n; ++a) {
				res += counts[P[a] - P[b] + P[c] + MAX];
			}
		}
		for (int b = 0; b <= n; ++b) {
			for (int a = b + 1; a <= n; ++a) {
				counts[P[b] - P[a] + P[c] + MAX]++;
			}
		}
	}
	map<int, int64_t> intervals;
	for (int i = 0; i <= n; ++i) {
		for (int j = i + 1; j <= n; ++j) {
			int sum = P[j] - P[i];
			if (intervals.find(sum) == intervals.end()) {
				intervals[sum] = 1;
			}
			else {
				++intervals[sum];
			}
		}
	}
	for (int i = 0; i <= n; ++i) {
		for (int j = i + 1; j <= n; ++j) {
			int sum = 2 * (P[j] - P[i]);
			map<int, int64_t>::iterator it = intervals.find(-sum);
			if (it != intervals.end()) {
				res -= 3 * (it->second - (sum ? 0 : 1));
			}
		}
	}
	res -= intervals[0];
	printf("%lld\n", res / 6);
	return 0;
}