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#include <bits/stdc++.h>
using namespace std;
vector <int> a{0}, pref{0};
map <int, int > m;



int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    for (int i = 0; i < n; i++) {
        int x;
        cin >> x;
        a.push_back(x);
        pref.push_back(pref[i] + x);
    }

    for (int i = 1; i <= n; i++) {
        int sum = 0;
        for (int j = i; j <= n; j++) {
            sum += a[j];
            m[sum]++;
        }
    }


    long long ile = 0;
    for (int i = 1; i <= n; i++) {
        for (int j = i; j <= n; j++) {
            for (int k = 1; k <= n; k++) {
                for (int l = k; l <= n; l++) {
                    if (i == k && j == l)
                        continue;

                    // case normal
                    int s1 = pref[j] - pref[i-1], s2 = pref[l] - pref[k-1];
                    int s = s1 + s2;
                    auto v = m[-1 * s];
                    ile += v;
                    if (s1 == -1 * s)
                        ile--;
                    
                    if (s2 == -1 * s)
                        ile--;
                }
            }
        }
    }
    cout << ile / 6;
    return 0;
}