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#include <cstdio>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
using namespace std;

int nextInt() { int n; scanf("%d", &n); return n; }

const int N = 500;
const int NN = N * (N + 1) / 2;
const int V = 1000000;

int a[N];
int cnt[V + V + 1];

int values[NN];
int vcnt;

int main() {
	//if (0)
	{
		int n = nextInt();
		for (int i = 0; i < n; ++i)
			a[i] = nextInt();
		int nn = 0;
		for (int i = 0; i < n; ++i) {
			int s = 0;
			for (int j = i; j < n; ++j) {
				s += a[j];
				int& count = cnt[V + s];
				if (0 == count)
					values[vcnt++] = s;
				++count;
			}
		}
	}

	if (0) {
		int test = 400;
		int test2 = test * (test + 1) / 2;
		for (int i = 0; i < test2; ++i) {
			int v = i - test2 / 2;
			values[i] = v;
			cnt[V + v] = 1;
		}
		vcnt = test2;
	}


	long long res = 0;

	if (cnt[V] >= 3)
		res = 1LL * cnt[V] * (cnt[V] - 1) * (cnt[V] - 2);

	for (int i = 0; i < vcnt; ++i) {
		int v = values[i];
		if (cnt[V + v] < 2)
			continue;
		if (v == 0)
			continue;
		if (v + v > V)
			continue;
		if (v + v < -V)
			continue;
		res += 3LL * cnt[V + v] * (cnt[V + v] - 1) * cnt[V - v - v];
	}

	for (int i = 0; i < vcnt; ++i) {
		int vi = values[i];
		for (int j = i + 1; j < vcnt; ++j) {
			int vj = values[j];
			int vk = 0 - vi - vj;
			if (vk != vi && vk != vj)
				res += 2LL * cnt[V + vi] * cnt[V + vj] * cnt[V + vk];
		}
	}

	res /= 6;
	printf("%lld\n", res);

	return 0;
}