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#include <bits/stdc++.h>
using namespace std;
using lint = long long;
using pi = array<lint, 2>;
#define sz(v) ((int)(v).size())
#define all(v) (v).begin(), (v).end()
#define cr(v, n) (v).clear(), (v).resize(n);
const int OFFSET = 10000000;
// 6 ABC + 3 AAB + AAA = n^3

int radix[OFFSET * 6 + 5];
#define rep(i, s, e) for (int i = s; i < e; i++)

int mult(int a, int b, int c) {
	if (a == b && b == c)
		return 1;
	if (a == b || b == c)
		return 3;
	return 6;
}

int mult(int a, int b) { return a != b ? 2 : 1; }

lint get_total(vector<int> sum) {
	lint ans = 0;
	int n = sz(sum);
	// case#15
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e, n) { ans += radix[sum[e] + sum[f] - sum[d] + 3 * OFFSET] * mult(e, f); }
		int a = d;
		radix[sum[a] + 3 * OFFSET] += 3;
	}
	// case#16
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(f, d + 1, n) { ans += radix[sum[d] + sum[f] + 3 * OFFSET]; }
		rep(a, 0, d + 1) {
			int b = d;
			radix[sum[a] + sum[b] + 3 * OFFSET] += 3 * mult(a, b);
		}
	}
	// case#17
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e, n) { ans += radix[sum[e] + sum[f] + 3 * OFFSET] * mult(e, f); }
		rep(a, 0, d + 1) {
			int b = d;
			radix[sum[a] + sum[b] + 3 * OFFSET] += 6 * mult(a, b);
		}
	}
	// case#3
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e, n) {
			int k = -2 * sum[d] + sum[e] + sum[f];
			if (k < -3 * OFFSET || k > 3 * OFFSET)
				continue;
			ans += radix[k + 3 * OFFSET] * mult(e, f);
		}
		rep(a, 0, d) {
			int b = d;
			radix[sum[a] - sum[b] + 3 * OFFSET] += 3;
		}
	}
	// case#7
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e + 1, n) {
			int k = 2 * sum[d] - sum[e] + sum[f];
			if (k < -3 * OFFSET || k > 3 * OFFSET)
				continue;
			ans += radix[k + 3 * OFFSET];
		}
		rep(a, 0, d + 1) {
			int b = d;
			radix[sum[a] + sum[b] + 3 * OFFSET] += 3 * mult(a, b);
		}
	}
	// case#1
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e + 1, n) ans += radix[sum[d] - sum[e] + sum[f] + 3 * OFFSET];
		rep(a, 0, n) rep(b, a + 1, d) radix[sum[a] - sum[b] + sum[d] + 3 * OFFSET] += 6;
	}
	// case#2
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d, n) rep(f, e, n) ans += radix[sum[d] + sum[e] + sum[f] + 3 * OFFSET] * mult(d, e, f);
		rep(a, 0, n) rep(b, a, d + 1) radix[sum[a] + sum[b] + sum[d] + 3 * OFFSET] += mult(a, b, d);
	}
	// case#4, 5, 6
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e + 1, n) ans += radix[-sum[d] + sum[e] + sum[f] + 3 * OFFSET] * 2;
		rep(e, d + 1, n) rep(f, e, e + 1) ans += radix[-sum[d] + sum[e] + sum[f] + 3 * OFFSET];
		rep(e, d, d + 1) rep(f, e + 1, n) ans += radix[-sum[d] + sum[e] + sum[f] + 3 * OFFSET];
		rep(a, 0, n) rep(b, a + 1, d) {
			int c = d;
			radix[sum[a] - sum[b] + sum[c] + 3 * OFFSET] += 6;
		}
	}
	// case#8,9,10
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		rep(e, d + 1, n) rep(f, e + 1, n) ans += radix[sum[d] - sum[e] + sum[f] + 3 * OFFSET];
		rep(a, 0, d) rep(b, a + 1, d) {
			int c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 12;
		}
		rep(a, 0, d) {
			int b = a, c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6;
		}
		rep(a, 0, d) {
			int b = d, c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6;
		}
	}
	// case#11, 14
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		// query
		rep(e, d, d + 1) rep(f, e + 1, n) ans += radix[-sum[d] + sum[e] + sum[f] + 3 * OFFSET];
		rep(a, 0, d) {
			int b = d, c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6;
		}
		rep(a, 0, d) rep(b, a, d) {
			int c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6 * mult(a, b);
		}
	}
	// case#12, 13
	memset(radix, 0, sizeof(radix));
	rep(d, 0, n) {
		// query
		rep(e, d + 1, n) rep(f, e, n) ans += radix[-sum[d] + sum[e] + sum[f] + 3 * OFFSET] * mult(e, f);
		rep(a, 0, d) rep(b, a, d) {
			int c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6 * mult(a, b);
		}
		rep(a, 0, d) {
			int b = d, c = d;
			radix[sum[a] + sum[b] - sum[c] + 3 * OFFSET] += 6;
		}
	}
	return ans;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	vector<int> a(n), sum(n + 1);
	for (int i = 0; i < n; i++) {
		cin >> a[i];
		sum[i + 1] = sum[i] + a[i];
	}
	lint total = get_total(sum);
	vector<int> v;
	for (int i = 0; i < n; i++) {
		for (int j = i; j < n; j++) {
			v.push_back(sum[j + 1] - sum[i]);
		}
	}
	map<int, int> mp;
	for (auto &x : v)
		mp[2 * x]++;
	for (auto &x : v) {
		if (x == 0)
			total += 2;
		if (mp.count(-x))
			total -= 3 * mp[-x];
	}

	cout << total / 6 << "\n";
}