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#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned int ui;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<long long> vll;
const ll LINF = 1e18;
const int INF = 1e9;
int cnt[6 * 500 * 20000 + 16];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin >> n;
    vi a(n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

    vi prefix_sums(n + 1);
    prefix_sums[0] = 0;
    for (int i = 0; i < n; ++i) {
        prefix_sums[i + 1] = prefix_sums[i] + a[i];
    }
    
    ll result = 0;
    // unordered_map<int, int> cnt;
    int shift = 3 * 500 * 20000 + 8;
    for (int j = 0; j <= n; ++j) {
        for (int i1 = 0; i1 <= n; ++i1) {
            for (int i2 = i1 + 1; i2 <= n; ++i2) {
                int sum_i = prefix_sums[i2] - prefix_sums[i1];
                int sum = sum_i + prefix_sums[j];
                result += cnt[sum + shift];
            }
        }

        for (int i1 = 0; i1 <= n; ++i1) {
            for (int i2 = i1 + 1; i2 <= n; ++i2) {
                int sum_i = prefix_sums[i2] - prefix_sums[i1];
                ++cnt[prefix_sums[j] - sum_i + shift];
                // cerr << "S_i=" << sum_i << " j,i1,i2=" << j << "," << i1 << "," << i2 << " S_j=" << prefix_sums[j] << ' ' << sum << ' ' << prefix_sums[j] - sum_i << " CNT=" << cnt[sum] << endl;
            }
        }
    }

    // cerr << result << endl;

    unordered_map<int, int> dupes_counter;
    ll cnt_dupes = 0;
    ll cnt_zeros = 0;
    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            int sum = prefix_sums[j] - prefix_sums[i];
            if (sum == 0) {
                ++cnt_zeros;
            }
            ++dupes_counter[2 * sum];
        }
    }

    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            int sum = prefix_sums[j] - prefix_sums[i];
            cnt_dupes += dupes_counter[-sum];
        }
    }

    // Cerr << dupes_counter[0] << endl;
    // cerr << result << endl;
    // cerr << cnt_dupes << endl;
    cout << (result - 3 * (cnt_dupes - cnt_zeros) - cnt_zeros) / 6 << endl;

    return 0;
}