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// #pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include <bits/stdc++.h>
using namespace std;

#define PB emplace_back
// #define int long long
#define ll long long
#define vi vector<int>
#define siz(a) ((int) ((a).size()))
#define rep(i, a, b) for (int i = (a); i <= (b); ++i)
#define per(i, a, b) for (int i = (a); i >= (b); --i)
void print(vi n) { rep(i, 0, siz(n) - 1) cerr << n[i] << " \n"[i == siz(n) - 1]; }

const int N = 500, M = 3e7;
int a, s[N + 5];
struct node {
	int s[M + M + 5];
	int& operator[](const int &n) {return s[n + M];}
} p;

signed main() {
	// freopen(".in", "r", stdin);
	// freopen(".out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> a;
	rep(i, 1, a) cin >> s[i], s[i] += s[i - 1];
	rep(i, 1, a) rep(j, 1, a) rep(k, j, a) ++p[s[i] + s[k] - s[j - 1]];
	ll ans = 0;
	rep(i, 1, a) {
		rep(j, 1, a) rep(k, j, a) {
			ans += p[-(-s[i - 1] + s[k] - s[j - 1])];
			// if(p[-(-s[i - 1] + s[k] - s[j - 1])]) cout << i << ' ' << j << ' ' << k << ' ' << -s[i - 1] + s[k] - s[j - 1] << endl;
		}
		rep(j, 1, a) rep(k, j, a) --p[s[i] + s[k] - s[j - 1]];
	}
	rep(i, 1, a) rep(j, i, a) if(s[j] - s[i - 1] == 0) --ans;
	ans /= 3;
	rep(i, 1, a) rep(j, i, a) {
		ans -= p[s[i - 1] - s[j]];
		++p[2 * (s[j] - s[i - 1])];
	}
	memset(p.s, 0, sizeof(p.s));
	rep(i, 1, a) rep(j, i, a) {
		ans -= p[2 * (s[i - 1] - s[j])];
		++p[s[j] - s[i - 1]];
	}
	ans /= 2;
	cout << ans;
	return cerr << endl << 1.0 * clock() / CLOCKS_PER_SEC << endl, 0;
}