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


int main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int n;
    cin >> n;
    vector <int> pref(n + 1);
    for (int i = 1; i <= n; i++) {
        cin >> pref[i];
        pref[i] += pref[i - 1];
    }

    vector <int> v;
    for (int i = 1; i <= n; i++) {
        for (int j = i; j <= n; j++) {
            v.push_back(pref[j] - pref[i - 1]);
        }
    }

    map <int, vector <int>> pos;
    for (int i = 0; i < v.size(); i++) {
        pos[v[i]].push_back(i);
    }

    int ans = 0;
    for (int i = 0; i < v.size(); i++) {
        for (int j = i + 2; j < v.size(); j++) {
            int s = (v[i] + v[j]) * (-1);

            auto it1 = lower_bound(pos[s].begin(), pos[s].end(), i + 1), it2 = lower_bound(pos[s].begin(), pos[s].end(), j);
            ans += it2 - it1;
        }
    }
    cout << ans << '\n';
}